Asthma

A published clinical study (Boskabady et al., 2007, Therapie) demonstrated bronchodilatory effects of ajwain decoction in asthmatic patients, comparable to theophylline. Preclinical studies confirm calcium channel-blocking antispasmodic mechanisms in tracheal smooth muscle. Traditional use for asthma is also well-documented.

ACA (1′-acetoxychavicol acetate) isolated from A. galanga significantly reduced ovalbumin-induced asthmatic airway inflammation in mice in a published PMC study. The compound modulates Th1/Th2 cytokine imbalance and reduces inflammatory infiltrate in bronchoalveolar lavage. Traditional use for respiratory conditions is also well-documented.

Andrographis paniculata and its diterpene andrographolide have anti-inflammatory properties targeting NF-κB and reducing Th2-driven airway inflammation in preclinical asthma models. Andrographolide inhibits expression of pro-inflammatory cytokines including IL-4, IL-5, and IL-13 relevant to eosinophilic asthma, and is traditionally used in Ayurvedic and TCM medicine for respiratory conditions.

Andrographolide is the principal diterpene lactone of Andrographis paniculata that inhibits NF-κB signaling, reduces Th2 cytokines (IL-4, IL-5, IL-13), and decreases eosinophilic airway inflammation in preclinical asthma models. It is among the most studied phytochemicals for NF-κB-mediated anti-inflammatory activity relevant to asthma.

Epidemiological studies report negative associations between apple intake and asthma prevalence and incidence. Apple flavonoids, particularly quercetin and catechins, have bronchodilatory and anti-inflammatory mechanisms relevant to asthma. A large London case-control study found dietary catechin and flavonol intake (from apples) associated with lower asthma risk.

Aster root has been used in TCM for asthma for over 2,000 years and is noted in ancient literary records for alleviating asthma. Preclinical studies show A. tataricus inhibits tracheal ring contraction and airway inflammation simultaneously, with bronchodilatory properties documented in animal models. No human RCTs on asthma have been published.

Astragaloside IV, the primary saponin from Astragalus membranaceus, reduces airway inflammation in preclinical asthma models by inhibiting NF-κB signaling and suppressing Th2 cytokine production. It is the compound responsible for many of astragalus root's documented anti-asthmatic effects.

Astragalus membranaceus has NF-κB inhibitory activity relevant to asthmatic airway inflammation, as documented in a PMC review of herbal medicines for asthma. It is traditionally used in TCM for respiratory conditions including asthma, where it is considered a lung-tonifying herb. Preclinical studies confirm astragaloside IV reduces airway inflammation in asthma models.

Baicalein, the aglycone flavonoid from Scutellaria baicalensis, inhibits NF-κB and STAT6 signaling pathways and reduces eosinophilic airway inflammation in asthma models. As the active metabolite of baicalin with superior bioavailability, it contributes to the anti-asthmatic activity documented for Baikal skullcap in preclinical studies.

Baicalin is a flavone glucuronide from Scutellaria baicalensis (Baikal skullcap) that inhibits NF-κB signaling and STAT6 activation, reducing Th2-mediated airway inflammation in asthma models. A PMC herbal medicines review confirmed baicalin's asthma-relevant NF-κB inhibitory activity. Baikal skullcap is traditionally used in TCM for respiratory conditions.

Baikal Skullcap (Scutellaria baicalensis) root contains baicalin and baicalein, flavonoids that inhibit NF-κB and STAT6 signaling and reduce leukotriene synthesis, addressing multiple inflammatory pathways in asthma. A PMC herbal asthma review confirmed baicalin/baicalein from Scutellaria baicalensis as mechanistically relevant NF-κB and MAPK inhibitors.

Epimedium and its bioactive compounds including icariin have been reviewed for respiratory disease management, with anti-inflammatory, antioxidant, and immunomodulatory mechanisms documented as relevant to asthma. A 2025 ScienceDirect comprehensive narrative review specifically examined Epimedium's effects on respiratory diseases including asthma. Traditional use for bronchitis and asthma is documented across multiple historical and ethnopharmacological sources.

O. basilicum extracts demonstrated immunomodulatory and anti-inflammatory effects in an ovalbumin-induced rat asthma model (BMC Complementary Medicine, 2019), reducing lung pathological changes. Its constituent linalool has bronchodilatory properties. Traditional use for asthma is documented across multiple cultures. No human clinical trials have been published.

A pharmacological mechanism study (Gilani et al., J Ethnopharmacol 2008) demonstrated that T. bellirica fruit exerts bronchodilatory effects via anticholinergic and calcium channel antagonist mechanisms, directly validating its traditional use in asthma. The fruit is listed for asthma in traditional Ayurvedic, Unani, Siddha, and Chinese medicine systems. Its antispasmodic properties on airway smooth muscle provide a credible mechanistic basis.

Multiple preclinical and some clinical studies support B. breve's role in reducing airway inflammation. The strain MRx0004 suppressed both neutrophil and eosinophil lung infiltration in a severe steroid-resistant asthma mouse model. A pediatric RCT using a Bifidobacteria mixture including B. breve M-16V significantly improved nasal symptoms and quality of life in children with pollen-induced allergic rhinitis and intermittent asthma. Mechanistically, B. breve appears to shift immune responses away from pro-allergic Th2 polarization.

Preclinical studies show B. lactis strains reduce ovalbumin-induced allergic asthma markers in mice, including IgE, airway inflammation, and Th2 cytokines, partly through tryptophan metabolism. Human evidence is limited to indirect support from respiratory allergy trials; dedicated clinical asthma RCTs are lacking.

Multiple RCTs in adult asthma patients show N. sativa (1–2 g/day seeds or 1 g/day oil, 3–12 weeks) significantly improved asthma symptoms and pulmonary function. Clinical reviews and a 2021 updated comprehensive review confirm bronchodilatory and preventive effects in asthmatic patients.

Preclinical studies have demonstrated antiasthmatic activity for A. scholaris leaf alkaloid extracts in guinea pig bronchoconstriction models induced by histamine. The ethanolic extract and isolated alkaloids reduced bronchospasm, supporting longstanding traditional use for asthma in Ayurvedic and Chinese medicine.

Borage seed oil GLA has been shown in a Phase 2 RCT to significantly improve clinical asthma outcomes including cough, dyspnea, and airway hyper-responsiveness. A separate clinical study demonstrated that borage and echium oils combined reduced leukotriene B4 generation by neutrophils from asthma patients. The mechanism involves inhibition of leukotriene biosynthesis.

GLA from borage oil suppresses leukotriene B4 synthesis in airway neutrophils, and a preliminary double-blind clinical trial found borage extract improved clinical findings of moderate asthma though not underlying airway inflammation. A 12-month RCT showed GLA supplementation raised DGLA in PMN phospholipids and reduced LTB4 production, though without statistically significant improvement in asthma scores.

Boswellia serrata resin and its boswellic acids have shown anti-asthmatic effects by inhibiting 5-lipoxygenase, reducing leukotriene synthesis and Th2 inflammatory responses. A double-blind, placebo-controlled clinical study of 80 asthma patients found 300 mg three times daily for six weeks significantly reduced asthma attack frequency and improved breathing capacity.

Boswellic acids, the active constituents of Boswellia serrata, inhibit 5-lipoxygenase and suppress leukotriene production, directly addressing key inflammatory pathways in asthma. Animal studies confirm suppression of Th2 cytokines, IgE, and airway hyperresponsiveness. They represent the mechanism behind clinical efficacy of Boswellia extracts in asthma.

Bromelain has demonstrated anti-inflammatory activity in animal models of allergic airway disease (AAD), attenuating airway inflammation and altering CD4+/CD8+ T lymphocyte ratios. It inhibits Th2 cytokines such as IL-4 and IL-13, which drive asthmatic inflammation. While direct large-scale human RCTs in asthma are lacking, preclinical and immunological evidence supports a scientifically plausible relationship.

Saikosaponin-A (SSA), isolated from B. falcatum, significantly inhibited passive cutaneous anaphylaxis and suppressed asthmatic bronchoconstriction in sensitized guinea pigs in a dose-dependent manner. MSKCC also notes animal study evidence for inhibitory effects against allergic asthma. Evidence is preclinical only.

Several clinical studies indicate butterbur extract can reduce asthma attack frequency and improve lung function parameters. Petatewalide B and petasin inhibit leukotriene biosynthesis and exhibit antispasmodic effects on bronchial smooth muscle, providing a plausible mechanism. Evidence is preliminary and limited in trial quality, but is supported by Memorial Sloan Kettering and RxList databases.

Caffeine is a weak bronchodilator chemically related to theophylline and has demonstrated measurable improvements in lung function in people with asthma. A Cochrane systematic review confirmed that caffeine modestly improves lung function for up to four hours in asthma patients. Its effect on airway reactivity is sufficient to confound pulmonary function testing.

Catalase activity in bronchoalveolar lavage (BAL) fluid is reduced in asthma patients compared to healthy controls, due to oxidative inactivation by peroxynitrite and other RNS. Asthma is associated with a global decrease in antioxidant defenses including catalase, superoxide dismutase, and glutathione, contributing to airway inflammation and remodeling.

A PubMed-indexed pharmacological study (PMID 28840614) demonstrated bronchodilator activity of A. aspera extract in ex vivo and in vivo models. Traditional use for asthma is extensive across South Asian and African systems.

Chrysin reduces allergic airway inflammation and airway remodeling in an OVA-induced chronic asthma mouse model by decreasing eosinophil counts, IL-4, IL-13, and total IgE, while restoring IFN-γ. It also inhibits airway smooth muscle cell proliferation via Akt/ERK pathway suppression. Evidence is entirely preclinical.

CLA has been investigated for airway benefits in asthma. A 2010 clinical trial found 4.5 g/day CLA for 12 weeks improved airway hyper-responsiveness in overweight mild asthmatics. A pediatric pilot RCT found modest dampening of cellular inflammation but no symptom improvement in atopic children.

Coleus forskohlii, the plant source of forskolin, has been traditionally used in Ayurvedic medicine for respiratory disorders. Forskolin's mechanism of raising cAMP via adenylate cyclase activation produces bronchodilation relevant to asthma. Clinical trials show reduced asthma attack frequency with oral forskolin, and preclinical studies confirm anti-inflammatory effects in asthma models.

Cordyceps sinensis mushroom has documented use in TCM for respiratory conditions including asthma, and preclinical/clinical evidence supports its bronchodilatory and anti-inflammatory effects. Cordyceps is listed in asthma-related databases among herbs studied for this condition. It contains adenosine and cordycepin, which relax bronchial smooth muscle.

Curcumin, the principal polyphenol of turmeric, inhibits NF-κB and MAPK signaling pathways that drive asthmatic airway inflammation. A combination trial including curcumin, Boswellia, and licorice root showed improvements in asthma patients. A 2025 systematic review confirmed curcumin inhibits NF-κB/MAPK signaling and improves allergic airway conditions.

Curcuminoids (the family of polyphenols in turmeric including curcumin, bisdemethoxycurcumin, and demethoxycurcumin) collectively inhibit NF-κB and MAPK inflammatory pathways central to asthmatic airway inflammation. They reduce Th2 cytokine production, IgE levels, and eosinophilic inflammation, with clinical evidence supporting their use as an adjunct in asthma management.

Alpha-tocopherol specifically inhibits allergic lung inflammation in clinical and animal studies by modulating protein kinase C alpha (PKCα) signaling in airways, opposing the pro-inflammatory effects of gamma-tocopherol. Human clinical studies examining vitamin E supplementation in asthma have been conducted, with α-tocopherol showing anti-inflammatory effects on allergic lung responses.

DHA, along with EPA, reduces arachidonic acid-derived pro-inflammatory mediators relevant to asthma and promotes synthesis of anti-inflammatory resolvins and protectins. Epidemiological evidence links higher DHA intake to reduced asthma risk. Pregnancy supplementation with DHA has been studied for reducing childhood asthma onset.

DHA and EPA exert anti-inflammatory effects in the lungs by modulating eicosanoid pathways, reducing leukotriene synthesis relevant to bronchoconstriction and airway inflammation. Omega-3s including DHA are recognized as potentially beneficial for managing asthma through their anti-inflammatory properties. Maternal omega-3 supplementation during pregnancy may protect children from developing allergies and asthma.

EGCG, the primary catechin in green tea, stabilizes mast cells, attenuates FcεRI (IgE receptor) signaling, and reduces airway inflammation in preclinical asthma models. A 2025 systematic review confirmed EGCG stabilizes mast cells and reduces airway inflammation in preclinical models, though clinical data in asthma remain limited.

Eicosapentaenoic acid (EPA) is an omega-3 fatty acid that competitively reduces leukotriene synthesis from arachidonic acid, addressing a key pathogenic mechanism in asthma. Multiple AHRQ-reviewed studies and a 2025 comprehensive systematic review confirm EPA modulates Th2 inflammatory responses relevant to asthma.

EPA, an omega-3 fatty acid, reduces pro-inflammatory leukotriene synthesis by competing with arachidonic acid, addressing a core inflammatory mechanism in asthma. Epidemiological and clinical data link higher EPA/DHA intake to lower asthma incidence and severity. EPA contributes to generation of anti-inflammatory resolvins that help resolve airway inflammation.

Ephedra (Ma Huang) has been used in Traditional Chinese Medicine for thousands of years to treat bronchial asthma, and its alkaloid ephedrine is a well-documented bronchodilator that acts on adrenergic receptors. Scientific literature confirms ephedrine's anti-asthmatic effects via beta-adrenergic stimulation and bronchial dilation. A PMC review confirmed Ephedra has multiple targets effective for asthma treatment.

Ephedrine is an alkaloid from Ephedra sinica that was historically the primary pharmaceutical bronchodilator for asthma before modern beta-2 agonists. It acts as a non-selective adrenergic agonist producing bronchial smooth muscle relaxation. Scientific literature confirms its anti-asthmatic effects via beta-adrenergic stimulation and it served as the foundation for modern asthma pharmacotherapy.

1,8-cineole (eucalyptol), the primary constituent of eucalyptus oil, has demonstrated anti-inflammatory activity in bronchial asthma in multiple double-blind, placebo-controlled trials. Oral cineole showed a significant steroid-sparing effect in steroid-dependent asthma patients. Its mechanism involves suppression of arachidonic acid metabolism and cytokine production in monocytes and T-lymphocytes.

Fish oil, rich in EPA and DHA, reduces pro-inflammatory leukotriene synthesis relevant to asthmatic airway inflammation. Clinical trials, including pediatric studies, have examined fish oil supplementation for asthma, with AHRQ evidence reviews noting its potential role. A clinical trial (NCT06560255) is examining fish oil in pregnancy for prevention of early childhood asthma in a large RCT.

Forskohlii root (Coleus forskohlii) and its active diterpene forskolin activate adenylate cyclase to raise intracellular cAMP, relaxing bronchial smooth muscle. A single-blind RCT in 40 asthma patients found oral forskolin (10 mg/day for 6 months) reduced asthma attacks in 40% vs. 85% in the cromoglycate group. It has traditional use in Ayurvedic medicine for respiratory disorders.

Pharmacological reviews identify 'alleviate asthma' as one of the documented activities of Forsythia suspensa compounds, particularly phillyrin, which is a PDE4 inhibitor. Phillyrin's cyclic AMP phosphodiesterase inhibitory activity is mechanistically relevant to bronchodilation and airway inflammation. Evidence is preclinical only.

Multiple preclinical studies demonstrate anti-asthmatic mechanisms including tracheal M-receptor antagonism, inhibition of Th2 cytokines and IgE, and reduction of eosinophilic infiltration. Chinese Pharmacopoeia preparations list anti-asthmatic use. One study showed BFP-TA attenuated airway remodeling via Wnt/β-catenin in asthma model rats.

Multiple controlled human studies from the University of North Carolina group show γT-enriched supplementation reduces sputum eosinophilia and endotoxin-induced neutrophilic airway inflammation in asthmatic volunteers. A 2023 randomized clinical trial also demonstrated attenuation of wood smoke–induced airway inflammation. Animal models consistently show γT prevents allergen-driven eosinophilia and mucous cell hyperplasia.

Garlic and its active constituent allicin exhibit anti-inflammatory properties relevant to asthma, including NF-κB inhibition, which is listed among potential asthma-relevant mechanisms in a PMC review of herbal asthma medicines. Garlic has traditional use for respiratory conditions and is listed among herbal treatments studied for asthma.

Ginger bioactives (6-gingerol, 6-shogaol) modulate Th1/Th2 cytokine balance, mast cell activity, and oxidative stress, with early clinical evidence in rhinitis and asthma. Ginger constituents have been documented in a Cochrane-referenced systematic review of herbal interventions for asthma, and a 2025 comprehensive review confirmed early clinical evidence in asthma.

Ginkgo biloba extract inhibits platelet-activating factor (PAF), a potent trigger of asthmatic bronchoconstriction, via its ginkgolide B constituent. It has been studied in at least one RCT with asthma patients and inhibits PAF-induced bronchoconstriction and airway inflammation. A murine study confirmed ginkgolide B suppressed Th2 cytokines and eosinophilia via ERK/MAPK pathway inhibition.

Green tea, rich in EGCG and other catechins, has anti-inflammatory and mast cell-stabilizing properties relevant to asthma. Epidemiological studies link green tea consumption to lower asthma incidence. Preclinical studies confirm its catechins reduce Th2 cytokines, airway eosinophilia, and histamine/leukotriene release in asthma models.

A double-blind, randomized, placebo-controlled trial (Emelyanov et al., European Respiratory Journal, 2002) in 46 patients with steroid-naïve atopic asthma found that 8 weeks of GLM lipid extract (Lyprinol, 200 mg omega-3 PUFAs/day) significantly reduced daytime wheezing, improved morning peak expiratory flow, and lowered exhaled hydrogen peroxide — a marker of airway inflammation. The proposed mechanism is inhibition of the 5-lipoxygenase and cyclooxygenase pathways that generate leukotrienes and prostaglandins, key mediators of airway inflammation. A separate 8-week double-blind RCT in 46 allergic asthma patients similarly reported improvement in wheezing and peak airflow.

H. spicatum has preclinical scientific evidence for anti-asthmatic activity, including bronchodilator, antihistaminic, and antioxidant effects in guinea pig and rat models. It is cited in Ayurvedic medicine as a primary anti-asthma agent (Shwasahara). One study concluded that 'beneficial effects in bronchial asthma could be due to balancing influence on prooxidant-antioxidant status and reducing airway inflammation.'

Hesperidin has demonstrated anti-asthmatic effects in animal models of allergic airway inflammation by suppressing eosinophil infiltration, Th2 cytokines (IL-4, IL-5, IL-13), and airway hyperresponsiveness. A 2023 review of hesperidin in inflammatory lung diseases specifically included a schematic representation of hesperidin's ability to reduce asthma symptoms in allergic airway models. Human RCT data for asthma are absent.

Hyssop has been used in Persian and Uyghur traditional medicine for asthma for centuries. A randomized triple-blind placebo-controlled trial (n=60) found hyssop syrup significantly improved FEV1, peak expiratory flow, and Asthma Control Test scores in patients with productive cough. Animal studies corroborate anti-inflammatory and immunomodulatory mechanisms.

A placebo-controlled double-blind clinical study evaluated a herbal composition containing Aegle marmelos fruit extract combined with Boswellia serrata and found significant alleviation of asthma symptoms. Traditional medicine also documents bael for asthma and acute bronchitis. The combination study provides the strongest evidence level.

A double-blind, placebo-controlled trial (Gupta et al., 1998; PubMed PMID 9810030) in 40 asthma patients demonstrated that 300 mg Boswellia gum resin three times daily for 6 weeks produced clinical improvement in 70% of treated patients vs. 27% on placebo. Improvements included increased FEV1, FVC, PEFR, and reduced attack frequency. The mechanism involves 5-LOX inhibition, reducing pro-inflammatory leukotrienes central to bronchoconstriction.

In vitro and in vivo animal studies have evaluated I. racemosa against multiple aspects of asthma, including bronchoconstriction, mast cell degranulation, eosinophilia, and airway vascular permeability. Petroleum ether extract demonstrated inhibition of histamine-induced bronchoconstriction and mast cell degranulation. The plant has deep traditional roots in Ayurveda as a bronchodilator for asthma (swasa roga).

Jujube extracts have demonstrated anti-allergic, antihistaminic, anti-anaphylactic, anti-inflammatory, and immunomodulatory activities in preclinical models relevant to asthma. Traditional use in respiratory conditions is documented in Asian and Middle Eastern medicine. No human clinical asthma RCTs are available.

Glutathione is central to airway antioxidant defense, and oxidative stress is a recognized mechanism in asthma pathophysiology. However, nebulized direct GSH administration has been shown in an RCT to cause paradoxical major bronchoconstriction in asthma patients. Glutathione treatment in children with allergic asthma using oral or non-nebulized routes has been studied with benefit, but route of administration is critical.

Murine asthma models consistently show that oral L. rhamnosus attenuates airway inflammation, hyperreactivity, and gut microbiome dysbiosis associated with allergic asthma. L. rhamnosus GR-1 prevented airway function deterioration in a birch-pollen mouse model. Human clinical evidence remains limited and mixed, with several RCTs showing no significant benefit.

L. salivarius LS01 has direct RCT evidence in pediatric asthma management. The PROPAM study, a double-blind RCT, found that L. salivarius LS01 (DSM 22775) combined with Bifidobacterium breve B632 significantly reduced the frequency and severity of asthma exacerbations in children. Preclinical data show L. salivarius PM-A0006 inhibits allergic airway responses in an OVA-sensitized mouse model.

Licorice root (Glycyrrhiza species) and its active compound glycyrrhizin have documented anti-asthmatic effects including inhibition of leukotriene synthesis, NF-κB suppression, and mast cell stabilization. A clinical trial found a combination formula including licorice root, curcumin, and Boswellia improved asthma control in 63 patients. Licorice has traditional TCM and Ayurvedic use for respiratory conditions.

Limonene has demonstrated efficacy in murine allergic asthma models, reducing key inflammatory cells (eosinophils, macrophages, neutrophils) and cytokines (IL-5, IL-13, IgE) in bronchoalveolar lavage fluid. It has immunomodulatory properties including suppression of TH2-driven allergic responses. Evidence is preclinical; no human asthma RCTs with limonene have been conducted.

Luteolin attenuates allergic asthma in preclinical models through suppression of airway inflammation, Th2 cytokine responses, and bronchial hyperreactivity. Multiple mechanistic pathways have been identified including NF-κB and PI3K/Akt inhibition.

Lycopene, a carotenoid antioxidant in tomatoes, has shown protective effects in exercise- and cold air-induced asthma in clinical studies. Lycopene supplementation attenuated post-exercise bronchoconstriction and reduced oxidative stress markers in asthmatic patients. It is listed as a natural intervention for asthma by multiple evidence-based sources.

Magnesium plays a recognized role in bronchial smooth muscle relaxation and is used intravenously in acute severe asthma exacerbations in clinical practice. A systematic review and meta-analysis of 8 RCTs (917 patients) found oral magnesium supplementation improved FEV1 at 8 weeks. Low serum magnesium levels correlate with greater asthma severity and poor bronchodilator response.

A clinical trial in 148 mild-to-moderate asthma patients taking corticosteroids found that magnolia extract improved asthma control and prevented extreme attacks. Magnolol also inhibits ovalbumin-induced allergic asthma by regulating T cell cytokines in animal models. Traditional use of magnolia bark for asthma is documented in TCM and Kampo.

Malabar nut (Adhatoda vasica) has been studied in animal models of asthma, with aqueous extracts shown to reduce airway resistance and inflammation. Its key alkaloids vasicine and vasicinone exert bronchodilatory and anti-inflammatory effects. A 2021 study in American Journal of Physiology-Lung demonstrated mechanistic evidence via HIF-1α suppression. Traditional use in Ayurveda for asthma is extensive and predates modern research.

Mangosteen xanthones have been identified as having anti-asthmatic properties in preliminary research, including via histamine H1 receptor blocking activity in isolated smooth muscle preparations. The anti-asthmatic property is cited by Memorial Sloan Kettering from preliminary data. Evidence is limited to laboratory/preclinical studies.

NAC is a glutathione precursor and mucolytic agent with well-documented use in respiratory conditions. It reduces mucus viscosity, scavenges reactive oxygen species, and has anti-inflammatory properties via NF-κB inhibition. NAC has been studied as an adjunct in asthma, particularly for its mucolytic and antioxidant benefits, and is listed among principal natural treatments for asthma in evidence-based reviews.

Omega-3 fatty acids (EPA and DHA) modulate the inflammatory pathways underlying asthma, competing with arachidonic acid to reduce pro-inflammatory leukotriene synthesis. AHRQ evidence reviews and multiple clinical studies have examined their role in asthma management. A 2025 comprehensive review confirmed omega-3s modulate Th2 responses and promote regulatory T cells with modest clinical benefits in asthma prevention.

Onion and its constituents relax tracheal smooth muscle, reduce bronchoalveolar inflammatory cell infiltration, and modulate Th1/Th2 cytokine balance in a manner relevant to asthma. Multiple preclinical models demonstrate anti-asthmatic activity, and epidemiological studies associate quercetin intake with reduced asthma incidence.

Perilla leaf extract suppresses allergen-driven Th2 cytokine responses and airway inflammation in preclinical asthma models. Traditional TCM use of perilla leaf and seed for asthmatic coughs and dyspnea is well-documented. Human bronchial epithelial cell studies confirm suppression of pro-allergic cytokines relevant to asthma pathogenesis.

P. kurroa has been investigated in several human clinical trials for bronchial asthma since the 1970s, with mixed but present evidence of benefit. Multiple RCTs and quasi-experimental trials exist; a Cochrane-referenced systematic review found one QED reported positive results. The compound androsin mechanistically prevents PAF-induced bronchial obstruction.

Clinical trials show pine bark extract (Pycnogenol, 100 mg/day) significantly improves lung function in asthma patients, increasing forced expiratory volume and reducing symptom severity by ~20% versus ~4.5% for placebo. It reduces airway inflammation by lowering leukotriene levels. It is also used traditionally for respiratory ailments.

Pine bark extract (Pycnogenol), rich in proanthocyanidins, has been evaluated in RCTs for asthma. A double-blind RCT in 60 children aged 6–18 with mild-to-moderate asthma found Pycnogenol supplementation significantly improved lung function and asthma symptoms compared to placebo. A follow-up adult trial confirmed adjunct benefit vs. inhaled corticosteroid alone.

Asthma is the most scientifically investigated indication for P. integerrima galls. Multiple preclinical studies confirm mast cell stabilization, 5-lipoxygenase inhibition, NF-κB suppression, and downregulation of Th2 cytokines (IL-4, IL-5, IL-13). A 2014 PubMed study (PMID 24556221) using spirometry and LPS-induced bronchial inflammation in rats, and a mouse ovalbumin allergic asthma model, provide in vivo evidence. Limited clinical observations in poly-herbal formulations show respiratory benefits.

Clinical studies in asthmatic patients treated with Plantago preparations show significant reductions in cough and wheezing, and improvements in FEV1 and FVC. A proof-of-concept study examined P. major seed in refractory asthma. Experimental models corroborate anti-inflammatory and bronchospasmolytic effects.

Platycodon root and platycodin D have demonstrated anti-asthmatic effects in animal models by reducing Th2 cytokines (IL-4, IL-5, IL-6, IL-13), eosinophilia, and NF-κB pathway activation in lung tissue. Platycodon is listed in traditional texts for bronchial asthma. Preclinical evidence is mechanistically strong; human trials are absent.

Platycodon grandiflorum is documented in TCM for asthma and wheezing. Multiple preclinical studies show it reduces eosinophilia, Th2 cytokines (IL-4, IL-5, IL-13), and airway hyperresponsiveness in OVA-induced asthma models via TLR4/NF-κB pathway inhibition. Fermented platycodon extract reduced airway inflammation and cough reflex sensitivity in guinea pig models.

A small clinical trial in 13 asthma patients found oral purslane extract (0.25 mL/kg, 5% boiled extract) produced pulmonary function improvements comparable to theophylline. Reviews confirm purslane has smooth muscle-relaxant and bronchodilatory properties via beta-adrenoceptor stimulation and muscarinic receptor inhibition. Quercetin, a key flavonoid, has documented antiasthmatic activity.

Pycnogenol is a proprietary pine bark extract standardized for oligomeric proanthocyanidins. A double-blind RCT in 60 children with mild-to-moderate asthma found significant improvement in lung function and symptom scores with Pycnogenol vs. placebo over 3 months. Adult trials also showed adjunct benefit to inhaled corticosteroid therapy.

Quercetin is a flavonoid that stabilizes mast cells, inhibits histamine release, and suppresses Th2-mediated inflammatory pathways relevant to asthma. Epidemiological studies link higher quercetin intake to lower asthma incidence. It inhibits 5-lipoxygenase and phosphodiesterase activities, reducing leukotriene synthesis and promoting bronchodilation-relevant cAMP elevation.

Ganoderic acid A, a reishi triterpene, significantly reduced OVA-induced asthma severity in a 2021 mouse study (Inflammation journal, PMID 34037898). Life Extension cites clinical studies supporting a role for reishi in calming asthma and allergic responses. TCM used reishi extensively for lung conditions including asthma. Human clinical trials are limited but preclinical and early clinical evidence support this relationship.

Rosmarinic acid has demonstrated anti-asthmatic activity in multiple preclinical models, reducing airway eosinophilia, IgE, Th2 cytokines, and airway hyperresponsiveness. One human clinical trial on seasonal allergic rhinoconjunctivitis provides direct human anti-inflammatory airway evidence. Preclinical mechanistic evidence shows RA acts via gut-lung axis microbiota modulation alongside direct lung anti-inflammatory pathways.

Two RCTs in allergic asthma patients demonstrate that 100 mg/day saffron for 8 weeks improved pulmonary function (FEV1, FVC, FEV1/FVC ratio), reduced clinical symptoms (dyspnea frequency, salbutamol use), and lowered inflammatory markers including hs-CRP and anti-HSP70. These are among the first dedicated human trials on saffron in asthma.

S. indicus has demonstrated bronchodilatory and mast cell stabilizing activities in preclinical studies, both of which are directly relevant to asthma pathophysiology. Traditional use in Ayurveda and Siddha for asthma-like respiratory conditions is well-documented.

Reduced SPM levels have been documented in asthmatic patients and are mechanistically linked to asthma pathogenesis. SPMs reduce mucus hypersecretion, bronchial hyperreactivity, and eosinophilic airway inflammation. A stable RvE1 analog has successfully completed human clinical trials for a related airway-mucosal condition, establishing the pharmacological principle.

Sulforaphane has been tested in multiple human asthma trials with mixed results. It improves bronchoprotective responses in asthmatics via Nrf2 and reduces allergen-driven remodeling in animal models. However, several RCTs found no significant change in pulmonary function or airway inflammation in asthma.

A. calamus rhizome extract has demonstrated bronchodilatory activity in preclinical models through multiple pathways. A 2010 PubMed-indexed Journal of Ethnopharmacology study confirmed bronchodilatory effects. Traditional use in asthma across Ayurveda, Unani, and Chinese medicine is extensively documented.

Theophylline is a xanthine alkaloid that has been a standard pharmaceutical treatment for asthma for decades, functioning as a bronchodilator and anti-inflammatory agent. Multiple clinical studies confirm it inhibits phosphodiesterase, raises cAMP, and suppresses late asthmatic reactions. It is recognized globally as a cost-effective option for chronic and acute asthma management.

A randomised triple-blind placebo-controlled clinical trial assessed Thymus vulgaris in children aged 5–12 with mild to moderate asthma exacerbation and found it ameliorated cough. Thymol's bronchospasmolytic action provides a pharmacological mechanism. Evidence is early-stage; a single RCT in a paediatric asthma exacerbation population is the primary clinical data.

T. kirilowii fruit extract reduced airway hyperresponsiveness, eosinophil infiltration, and airway inflammation in an ovalbumin-sensitized murine asthma model (PMC, 2025). Traditional use in TCM and Ayurveda for asthma and wheezing is also documented. All current scientific evidence is animal-based; no human clinical trials have been published.

Turmeric (Curcuma longa) and its curcuminoids have documented anti-asthmatic effects through inhibition of NF-κB and MAPK inflammatory pathways, reduction of leukotriene synthesis, and suppression of Th2-mediated airway inflammation. Turmeric has traditional use in Ayurvedic and Traditional Chinese Medicine for respiratory complaints including asthma.

Tylophora indica (Indian ipecac) has traditional use in India for bronchial asthma and has been evaluated in multiple clinical trials. Several controlled studies demonstrated moderate-to-complete relief of asthma symptoms with tylophora leaf administration. It is listed as a 'principal proposed natural treatment' for asthma by EBSCO and other evidence-based sources.

Tylophorine is the primary alkaloid of Tylophora indica responsible for its anti-asthmatic properties. It has immunomodulatory effects including suppression of Th2-mediated inflammation and has been studied in relation to asthma, being the active constituent behind tylophora leaf's documented clinical effects in bronchial asthma trials.

Clinical trials and systematic reviews have examined vitamin C in asthma, particularly in infection-triggered and exercise-induced subtypes. A systematic review found that 1 g/day vitamin C reduced asthma attacks by 78% in one Nigerian RCT of respiratory-infection-triggered asthma, and a cross-over study found 5 g/day reduced bronchial hypersensitivity by 52 percentage points. Evidence remains limited by small trial populations and inconsistent designs.

Vitamin D deficiency has been consistently associated with increased asthma exacerbations and reduced lung function. Multiple RCTs and meta-analyses support its role in reducing asthma attack frequency and modulating immune responses. A 2024 RCT in adults with mild-to-moderate asthma found vitamin D3 supplementation significantly improved FEV1:FVC ratio compared to placebo.

Vitamin D3 (cholecalciferol) is the animal-derived form of vitamin D with well-documented roles in asthma management, including reducing exacerbation frequency and modulating Th2-driven airway inflammation. A 12-week RCT in adult asthmatics found 125 µg/day vitamin D3 significantly improved FEV1:FVC ratio vs. placebo. Meta-analyses support its adjunct role in asthma treatment.

Yarrow is used in traditional medicine specifically for overactive respiratory conditions including asthma, and its bronchodilatory mechanism — calcium channel-dependent tracheal smooth muscle relaxation — has been demonstrated in guinea pig models. Evidence is preclinical only.

The leaf juice and essential oil of A. spectabilis are traditionally used for asthma in Himalayan and Indian folk medicine. Multiple ethnobotanical surveys from Nepal list asthma as a documented traditional indication. Preclinical bronchodilatory evidence supports the plausibility of this use.

Adrenal cortex extract was used as a mainstream medical treatment for asthma in the early 1900s, before synthetic corticosteroids were developed. This constitutes documented historical medical use rather than evidence from modern clinical trials. Contemporary OTC adrenal cortex supplements are not clinically validated for asthma management.

Agrimony has traditional use in some European and Asian folk medicine systems for respiratory complaints including asthma, primarily attributed to its anti-inflammatory, expectorant, and immunomodulatory properties. This use is documented in ethnomedicinal literature but lacks clinical trial support.

Anemarrhena is listed in traditional texts for 'cough type asthma' and is used in TCM formulas for respiratory conditions characterized by heat, wheezing, and dry cough. Its anti-inflammatory properties and lung-moistening actions provide plausible mechanism for asthma-relevant effects.

Apricot kernel (xing ren) is a key ingredient in TCM anti-asthmatic formulas, particularly Ma Xing Shi Gan Tang. TCM pharmacology describes its ability to relax bronchial smooth muscles and calm wheezing. Amygdalin from the kernel has demonstrated anti-asthmatic activity, and the enzyme amygdalase stimulates the respiratory center. Traditional use is well-documented; clinical RCT evidence for the kernel alone is limited.

Ashwagandha is documented in Ayurvedic medicine as a treatment for bronchitis and asthma. A 2025 preclinical biorxiv study showed withaferin A reduces pulmonary eosinophilia and IL-25 in a mouse allergic airways model. No human RCTs for asthma have been published; the evidence base remains traditional and preclinical.

Multiple traditional medical systems (European folk medicine, Chinese medicine, Ayurveda) documented asparagus for asthma. A. cochinchinensis is listed in the Chinese Pharmacopoeia specifically for asthma. In ancient Eastern and Greek medicine, asparagus was used as a tonic for ailments including asthma. No modern clinical trial evidence exists.

Bamboo sap (bamboo manna/zhuli) is used in traditional Indian and Chinese medicine for asthma, coughs, and lung conditions. Vanshlochan (tabasheer) is listed in Siddha and Unani materia medica for asthma treatment. These uses are well-documented across multiple traditional medical systems but lack clinical trial evidence.

Treatment of asthma is a well-documented traditional use of baobab leaves across sub-Saharan Africa. Leaf preparations are consumed orally or as inhalations in multiple countries for respiratory complaints including asthma, cough, and respiratory difficulty. The HerbalGram ethnopharmacological review and the ECHOcommunity review both document leaf preparations specifically for asthma. No clinical trials have evaluated baobab for asthma endpoints.

Bayberry appears in traditional records for asthma, both in TCM and in North American folk medicine where it was an ingredient in composition powder used for asthma and chest complaints. No clinical evidence supports this use.

In guinea pig and pig models, beta-sitosterol reduced asthmatic parameters including eosinophil counts, Th2 cytokines (IL-4, IL-5, IL-6, TNF-α), and histamine levels in lung tissue. The proposed mechanism is modulation of Th2 cytokines and inhibition of histamine secretion. No human clinical trials in asthma patients have been conducted.

Black spruce is used in aromatherapy for asthma support. It is listed in the Encyclopedia of Essential Oils for asthma and cough, and referenced in the British Herbal Pharmacopoeia for respiratory indications. Bornyl acetate has published anti-inflammatory activity in lung models. Care is needed as α-pinene may be a mild irritant for sensitive individuals.

C. crista is listed in traditional Ayurvedic and South Asian ethnomedicinal sources for treatment of asthma and respiratory disorders. The Unani system specifically attributes anti-asthmatic properties to the plant. No controlled preclinical or clinical studies specifically examining asthma have been identified.

Historical pharmacological texts and traditional medical systems document camphor's use for asthma and spasmodic cough. Traditional use involves inhalation of camphor vapor. Modern clinical evidence for camphor in asthma is absent, and camphor-containing products carry warnings for use in patients with asthma.

Cardamom has centuries of traditional use in Ayurvedic and South Asian medicine for asthma management. Its key volatile compound 1,8-cineole has documented bronchodilatory effects in pharmacological studies (relaxing airway smooth muscle), providing mechanistic plausibility. Human clinical trials specifically for cardamom in asthma management are absent.

Cat's claw is documented as an antiasthmatic agent in Peruvian and Brazilian traditional medicine and is listed as such in WHO-recognized traditional use databases. The 2024 Frontiers systematic review confirms it is 'widely used in Peruvian and Brazilian traditional medicine as an anti-inflammatory, antinociceptive, and antiasthmatic agent.' A preclinical meta-analysis includes asthma among the animal models studied. No human clinical trials for asthma exist.

Chen Pi is traditionally used in TCM for asthma-pattern presentations involving excessive phlegm and airway constriction. Its alkaloids have demonstrated anti-asthmatic activity preclinically, and flavonoids reduce IgE and Th2-type cytokines relevant to allergic asthma.

Chickweed is recorded across multiple herbal traditions—European, Indigenous North American, and TCM—as an antiasthmatic herb, with its expectorant and demulcent properties considered relevant to asthma management. The PMC pharmacological review and others document this use. No clinical asthma trials exist.

Clerodendrum indicum root is one of its most prominent traditional uses across Ayurveda, Unani, and Southeast Asian folk medicine systems. The pounded root, often combined with ginger, is taken as a decoction for asthma and related pulmonary complaints. Laboratory work has isolated a bronchodilatory component from the plant, providing partial mechanistic support, but no human clinical trials have been conducted.

Clove essential oil is cited in pharmacological reviews as having traditional use in asthma management, attributed to eugenol's bronchodilatory, anti-inflammatory, and antispasmodic properties. Human clinical trials in asthma patients are lacking.

Coltsfoot has a long tradition of use for asthma in both European and Chinese herbal medicine. One small uncontrolled study in convalescent asthmatics included coltsfoot in a multi-herb decoction with some benefit reported. Evidence remains largely traditional; no rigorous clinical trials exist for coltsfoot alone.

Wild yam and Dioscoreae Rhizoma are documented in traditional medicine—including the Chinese Pharmacopoeia and MSKCC monograph—as used for asthma and coughs, attributed to expectorant and antispasmodic properties on respiratory smooth muscle. Clinical evidence is absent.

Asthma is one of the three principal proposed traditional uses of elecampane, listed alongside chronic respiratory diseases and poor digestion by EBSCO Research Starters. Its use for asthma is documented in ancient Greek, Ayurvedic, TCM, and Western herbalism. No controlled clinical trials exist.

Asafoetida is a traditional Ayurvedic, Unani, and European remedy for asthma. Its antispasmodic, bronchodilatory, and expectorant properties—mediated by elimination of volatile oil through the lungs and tracheal smooth-muscle relaxation—provide pharmacological plausibility. Animal smooth-muscle studies support bronchodilatory effects.

Feverfew has traditional documentation for use in asthma and breathing difficulties. The PMC systematic review, NCCIH, and historical Dioscorides accounts all reference respiratory use. No clinical trials exist for this indication.

C. speciosa is documented in TCM texts as a treatment for asthma and related respiratory complaints. The PMC 2024 review of medicinal quinces specifically notes traditional use for asthma and colds. No pharmacological studies investigating asthma-specific mechanisms or outcomes for C. speciosa have been identified.

Fulvic acid has a documented traditional folk medicine history for treating asthma. The anti-inflammatory mechanism—suppression of overactive immune cells—is scientifically plausible and noted in peer-reviewed reviews, but human clinical trials for asthma are absent.

Ganoderma lucidum has a long traditional use for cough and asthma relief in Chinese medicine, described as 'tonifying the lung.' Preclinical evidence shows polysaccharides downregulate alveolar macrophage signalling in asthmatic rats and modulate Th2 immune responses in allergic asthma models.

G. littoralis is documented in TCM and Korean traditional medicine for respiratory conditions including rhinitis and asthma. The PMC 2019 systematic review records traditional use for asthma as part of respiratory disease management. No dedicated asthma pharmacology or clinical studies were identified.

Goldenrod is listed as a traditional remedy for asthma in the German Commission E, the A.D.A.M. database, and ethnobotanical records. Its antispasmodic properties relevant to smooth muscle could theoretically benefit bronchospasm. No clinical trials have evaluated goldenrod for asthma.

Traditional Ayurvedic and Unani medicine use amla for respiratory conditions including asthma. A pilot clinical study evaluated amla extract for 'cardio-respiratory improvement' in smokers. Mechanistic bronchodilatory and anti-inflammatory properties provide biological plausibility.

GMT's traditional use for bronchial asthma is specifically documented in multiple peer-reviewed ethnobotanical reviews and the 2023 Herba Sideritis systematic monograph. Balkan traditional medicine has used GMT as a broncho-dilatory and expectorant preparation for asthma. No clinical RCT in asthmatic patients has been published.

Gymnema sylvestre is documented in Ayurvedic texts as a remedy for asthma and bronchitis, attributed to an antitussive (cough-suppressing) action. A 2026 herbal reference (Herbal Reality) notes this antitussive property with literature citations. No human clinical trials for asthma exist.

H. antidysenterica bark is listed for asthma in British Materia Medica and in other traditional uses across Asian ethnomedicine. Modern Ayurveda also suggests the herb for bronchopneumonia and asthma. Anti-inflammatory mechanisms are pharmacologically plausible but no clinical trials exist.

Horehound has been used traditionally for asthma since ancient times, mentioned by Roman and 19th-century American Eclectic physicians. Its antispasmodic activity on bronchial smooth muscle provides mechanistic plausibility. No controlled clinical trials for asthma have been conducted.

H. italicum EO is traditionally used in Mediterranean folk medicine for asthma and bronchial conditions. Its documented anti-inflammatory activity (COX/LOX inhibition, leukotriene suppression) is mechanistically relevant to asthmatic airway inflammation, but no clinical trials exist.

Acacia nilotica has traditional use for respiratory complaints including asthma across South Asian and African traditional medicine systems. The antispasmodic and anti-inflammatory properties of A. nilotica provide a pharmacological rationale. The PMC 2024 review acknowledges asthma as a traditional use with limited scientific evidence.

H. indicus is documented in Ayurveda, Siddha, and Unani medicine and in Indian folk medicine for asthma and dyspnea. Anti-asthmatic activity is listed among the pharmacological properties demonstrated in preclinical studies. Traditional preparations include root decoction and infusion for respiratory conditions.

T. cordifolia is documented in Ayurvedic and ethnobotanical literature as a traditional treatment for asthma ('Shwasa roga'). Classical texts cite its use, and multiple ethnomedicinal surveys confirm it. Preclinical data suggest anti-inflammatory and bronchial smooth muscle-relaxing effects, but human clinical trials for asthma as a primary endpoint do not exist.

In traditional Indian medicine, including Ayurveda and folk medicine from Kerala and Tamil Nadu, indigo leaves and roots are used for asthma via decoctions and root-pepper preparations. The anti-inflammatory properties of the plant constituents are mechanistically relevant. No human clinical trials exist.

Syringa species are documented in traditional Chinese medicine as treatments for asthma, cited in the BMC Chemistry phytochemical review. Mechanistically, anti-inflammatory and bronchodilatory-plausible activities of lilac's phenolic constituents provide biological rationale, though no human clinical evidence exists.

Asthma is lobelia's most historically prominent indication. Native Americans smoked lobelia to treat asthma, and Eclectic physicians made it a primary botanical for asthma management. Alpha-lobeline relaxes bronchial smooth muscle and stimulates respiratory drive. Despite a plausible mechanism, Healthline and MSKCC confirm no human clinical trials have demonstrated efficacy.

Marjoram is documented in traditional folk medicine for respiratory complaints including asthma-like conditions. Its antispasmodic and anti-inflammatory properties have been cited in relation to bronchospasm.

Milkweed, particularly A. tuberosa and A. syriaca, has extensive traditional use for asthma. It was listed in the US Pharmacopeia partly for asthmatic conditions and was used by multiple Indigenous North American tribes. The antispasmodic and expectorant properties were considered relevant to asthma management. No clinical evidence exists.

Momordica charantia is cited in Ayurvedic and folk medicine traditions across Asia and Africa as a remedy for asthma and respiratory conditions. The fruit is described as useful for 'asthma' in traditional texts. No clinical human trials have investigated this indication.

Mulberry root bark (Sang Bai Pi) is a classical TCM remedy for wheezing and dyspnoea closely resembling asthma presentations, documented in the Chinese Pharmacopoeia for 'draining Lung heat and relieving asthma.' Preclinical anti-inflammatory and bronchodilatory properties are reported.

Mullein has a centuries-old reputation as a remedy for asthma, used to relax bronchial spasms and clear airway mucus. A 2012 PMC study demonstrated antispasmodic activity of Verbascum thapsus extract in intestinal smooth muscle preparations, supporting a plausible mechanism. No modern RCTs in asthma patients have been completed.

Mustard plasters applied to the chest were historically prescribed by doctors for asthma in the early 20th century. The mechanism invoked was bronchodilatory effects from increased chest circulation and AITC vapors. No modern clinical evidence supports this use, and AITC can be an airway irritant at high doses.

TC is documented in both classical Ayurvedic texts and the comprehensive PMC review as a traditional remedy for asthma, chronic cough, and dyspnea. Preclinical evidence suggests potential effectiveness in IgE-dependent conditions like bronchial asthma. Human clinical trials for asthma are absent.

Myrrh is documented in TCM and Western herbal traditions for asthma, cough, and lung congestion. The anti-inflammatory properties relevant to airway inflammation provide mechanistic plausibility. No clinical trial evidence for asthma specifically exists.

Neem is listed as a traditional treatment for respiratory disorders including asthma in Ayurvedic medicine, documented in the ScienceDirect overview. Anti-inflammatory properties (COX/LOX inhibition reducing leukotrienes relevant to airway inflammation) provide mechanistic plausibility. Human clinical trials for asthma are absent.

Nettle has been used traditionally for respiratory complaints including asthma and coughs across multiple ethnomedicinal traditions including Peru and Brazil, as documented by EMA assessment. The antihistamine and mast-cell-stabilizing activity of nettle flavonoids provide a theoretical mechanism. Clinical evidence specific to asthma is absent; the respiratory RCT data pertain to allergic rhinitis, not asthma.

Ophiopogon japonicus is a component of traditional and modern TCM formulas used for asthma, chronic bronchitis, and COPD, employed for its lung-moistening and phlegm-resolving properties. Direct clinical evidence for O. japonicus monotherapy in asthma is not available.

Asthma is listed among the traditionally documented uses of Citrus sinensis across multiple traditional medicine systems. Orange peel preparations were used to ease bronchospasm and respiratory distress. Laboratory evidence suggests anti-inflammatory flavonoids may modulate airway inflammation, but clinical RCT evidence for orange in asthma is absent.

Oregano is documented in traditional medicine across multiple cultures — including Turkish and Mediterranean traditions — as a treatment for asthma and respiratory spasm. Its expectorant, antispasmodic, and anti-inflammatory properties provide biological plausibility. No human clinical trials evaluating oregano for asthma have been published.

P. orientalis leaves are documented in the Chinese Pharmacopoeia and classical materia medica as used in combination with other herbal medicines for asthma treatment. This is one of the primary traditional respiratory indications listed in the Chinese Pharmacopoeia (2010). Anti-inflammatory activity in airway disease models provides mechanistic plausibility.

P. foetida is used for asthma in multiple traditional medical systems including Ayurveda, Chinese traditional medicine, and Vietnamese folk medicine. The plant is specifically listed for asthma in traditional Chinese and Indian materia medica alongside anti-inflammatory activity relevant to asthmatic pathophysiology.

Parsley's volatile oils and anti-inflammatory flavonoids have some traditional application in respiratory conditions, and its high vitamin C content may reduce airway oxidative stress. Traditional ethnopharmacological references include respiratory conditions in parsley's documented uses, though clinical evidence for asthma is absent.

Asthma is a documented traditional use of feverfew across multiple authoritative sources including the PMC systematic review, NCCIH, and historical European herbalism. The anti-inflammatory and antispasmodic properties of parthenolide provide mechanistic plausibility. No clinical evidence exists for this indication.

Peach kernel (Tao Ren) is classified in TCM as antiasthmatic and enters the Lung channel. Multiple botanical references list asthma among the seed's indications. Expectorant and antitussive properties are attributed to the kernel. No clinical evidence exists.

Plantain is listed in traditional medicine globally for asthma treatment. Preclinical studies in asthmatic rats with P. major extract show reduced lung pathology. P. lanceolata shows antispasmodic activity relevant to bronchoconstriction. No human RCT for asthma specifically has been published.

P. tenuifolia has been used in traditional folk medicine for thousands of years as an expectorant for bronchial asthma. Multiple TCM and ethnomedical references document this use, and the Chinese Pharmacopoeia assigns it anti-asthmatic properties. No clinical trials specifically on asthma have been published.

Polygala root is listed in the Chinese Pharmacopoeia as being 'systematically utilized in anti-asthmatic formulations' in TCM practice. Traditional use for asthma-like respiratory conditions spans centuries. Preclinical evidence for anti-asthmatic mechanisms is limited; human trials are absent.

Multiple Papaver species have documented traditional use for asthma across Unani, Indian, Turkish, and folk medicine systems. P. somniferum is specifically listed for cardiac asthma in Unani texts. Antispasmodic alkaloids such as papaverine provide a mechanistic basis for bronchial smooth muscle relaxation.

Traditional use of prickly pear for bronchial asthma is documented in Korean and Latin American medicine. The Pollinator.org fact sheet records its use for dyspnea. No clinical trials examining Opuntia for asthma outcomes have been published.

Ayurvedic texts and ethnobotanical records document P. marsupium heartwood use for asthma. A PMC-published MDPI study (2022) explicitly notes this traditional application.

Punarnava has documented traditional use in Ayurveda for asthma, cough, and breathing disorders, and is classified with expectorant and anti-histaminic properties. An ethanolic extract study in histamine aerosol-challenged animals showed protection against preconvulsive dyspnea at 100–400 mg/kg, suggesting bronchodilatory or H1-blocking activity. Human clinical evidence is absent.

Asthma is one of the most consistently documented traditional indications for red clover across multiple herbal traditions, including European, Chinese, and North American medicine. The plant was used for its antispasmodic effects on bronchial smooth muscle. No clinical trial evidence for asthma has been identified.

Ceanothus americanus has been used for asthma in Native American medicine and is specifically listed in Eclectic materia medica (King's American Dispensatory) and Plants for a Future as a traditional remedy for asthmatic conditions. Its antispasmodic and expectorant properties underlie this use. No human clinical trials exist.

Rehmannia has a documented traditional indication for asthma, listed in the Restorative Medicine clinical monograph and the Herbal Reality evidence database. The NDNR clinical review notes that clinical trials have found uncured Rehmannia produced therapeutic effects in asthma. Its anti-allergic mast cell and immune-modulating properties provide a plausible mechanistic rationale.

Rehmannia is listed in TCM monographs for asthma within the context of autoimmune and allergic respiratory conditions. The Restorative Medicine monograph and multiple practitioner references include asthma among its traditional indications. Anti-allergic and immunomodulatory actions provide a rationale, but clinical trial evidence is lacking.

In TCM, schisandra is traditionally listed for asthma, cough, and wheezing, appearing in ancient texts including the Shen Nong Ben Cao Jing and being listed as a treatment for 'cough, asthma and phlegm.' Official TCM indications include chronic cough and dyspnea. No modern clinical trials specifically for asthma have been conducted.

Slippery elm has been listed in traditional herbalism as a remedy for asthma and other upper respiratory complaints, attributed to its expectorant and mucosal-soothing properties. No clinical evidence supports this use, and it is not recognized in any evidence-based respiratory guideline.

Sunflower seeds and preparations have been recorded in traditional herbalism as treatments for pulmonary affections including asthma-related conditions. The seeds' expectorant properties and anti-inflammatory phytochemicals provide some mechanistic rationale. No clinical trials have examined sunflower specifically for asthma endpoints.

Bronchial asthma is among the traditional indications of Swertia chirayita documented in Ayurvedic texts, the Indian Pharmaceutical Codex, and multiple ethnopharmacological reviews. Airways modulatory effects have been noted in pharmacological literature. No human clinical trials for asthma are available.

Tartarian aster has been used in TCM for over 2,000 years to treat cough, wheezing, and asthma. The herb is included in the Bu Fei Soup formula, a classic remedy for asthma due to Lung Deficiency. Modern preclinical research identifies bronchial smooth muscle relaxation as a mechanistic basis. Human clinical trials are lacking.

Thyme has a long-standing traditional use for asthmatic symptoms and wheezing across European and Middle Eastern folk medicine. Preclinical evidence shows thyme oil modulates Th2 cytokines, IgE, and airway inflammation in an ovalbumin-induced rabbit asthma model. Human clinical trial evidence is absent; thymol's bronchospasmolytic properties support the mechanistic plausibility. Some historical formularies, including the WHO monograph context, mention asthma as a traditional indication.

Tinospora is described in traditional Indian and Ayurvedic texts as a remedy for asthma, cough, and respiratory ailments. It is cited as the 'best remedy for respiratory tract diseases' in ethnomedicinal reviews. Anti-allergic and anti-inflammatory properties provide mechanistic plausibility.

Watercress is documented as a traditional remedy for asthma across multiple folk medicine systems including Moroccan, Indian, and European traditions. A PMC-indexed narrative review confirms watercress is a traditional treatment for asthma. No human clinical RCT for asthma as a primary endpoint has been conducted with watercress.

Wheatgrass is documented in Ayurvedic and naturopathic traditions as a remedy for asthma. Chlorophyll's anti-inflammatory properties and potential oxygenation effects are cited mechanistically. No human clinical trial has evaluated wheatgrass for asthma.

Desiccated adrenal glandular extracts were among the earliest documented remedies used for asthma paroxysms, with historical accounts from the late 19th century describing relief of asthma attacks using 'grains of the desiccated gland substance.' The mechanism was later understood to be cortisone and epinephrine content, active principles since displaced by synthetic agents. Modern glandular products no longer contain meaningful hormone levels, eliminating the original pharmacological basis.

Wood betony has documented traditional use for respiratory conditions including asthma, attributed to its expectorant and bronchial-relaxing properties. This appears in folk and historical herbal records without modern clinical evidence.

Traditional healers in northern New Mexico brew yucca leaf tea to treat asthma, a use documented across multiple ethnobotanical sources including Encyclopedia.com and the 2023 PMC phytochemical review. This use is recorded specifically among New Mexico folk healers and some Native American tribes. No clinical trial has evaluated yucca for asthma.

Asthma is listed as a traditional indication for Z. armatum in South Asian ethnobotany, and Z. caribaeum is traditionally used for asthma in the Caribbean. The antispasmodic and anti-inflammatory pharmacology of the genus provides indirect mechanistic support, but no clinical studies have been performed.