Lung Health

Ajwain has demonstrated bronchodilatory and antitussive effects in both human clinical and animal studies. The 2007 Boskabady clinical study in asthmatic patients and multiple guinea pig antitussive studies constitute scientific evidence for lung-relevant pharmacological activity.

Alantolactone is a sesquiterpene lactone from Elecampane (Inula helenium) root with documented expectorant, antitussive, and antimicrobial properties relevant to respiratory health. It relaxes tracheal smooth muscle and has shown activity against respiratory pathogens including Mycobacterium tuberculosis.

Higher serum alpha-carotene levels are significantly associated with lower risk of lung cancer mortality in multiple prospective epidemiological studies, in contrast to supplemental beta-carotene which increased lung cancer risk in smokers in RCTs. A 2014 NHANES III-based study (N=10,382) found high serum alpha-carotene significantly associated with reduced lung cancer death. A Japanese nested case-control study found alpha-carotene's highest quartile associated with an OR of 0.41 for lung cancer death in men. All evidence is observational.

Andrographis paniculata is widely used in Asian traditional medicine for respiratory infections and is supported by clinical evidence for reducing symptoms in viral upper respiratory infections. Its active compound andrographolide has demonstrated anti-inflammatory and antiviral properties relevant to lung and airway health.

Andrographolide is the principal bioactive diterpenoid lactone from Andrographis paniculata, with clinical and preclinical evidence for reducing airway inflammation, suppressing NF-κB-mediated cytokine production, and supporting recovery from respiratory infections. Animal and in vitro studies demonstrate protection against lung injury.

Anemarrhena and timosaponin AIII have been shown in animal models to significantly inhibit LPS-induced acute lung inflammation, reducing alveolar wall thickening, inflammatory cell infiltration, and pro-inflammatory cytokines. The herb is also traditionally used for lung heat, dry cough, and lung infections.

Epidemiological studies consistently show positive associations between apple consumption and lung function. A cohort study of 2,512 middle-aged men found lung function 138 mL higher in those eating 5+ apples per week versus non-consumers, a finding attributed to apple's flavonoid content.

Aster root is one of the most extensively documented TCM herbs for lung support, with over 2,000 years of pharmacopeial use and multiple preclinical studies demonstrating antitussive, expectorant, anti-inflammatory, and acute lung injury-protective effects. Animal and network pharmacology studies support inhibition of inflammatory cytokines and protection of vascular endothelial cells in the lungs.

Astragalus (Astragalus membranaceus) has been used in Traditional Chinese Medicine to strengthen the lungs for millennia. A 2022 meta-analysis of 25 RCTs (n=1,762) found astragalus-containing prescriptions significantly reduced radiation-induced lung injury incidence, improved cure rate, alleviated breathing difficulties, and reduced inflammatory factors.

Baicalein is the aglycone form of baicalin from Scutellaria baicalensis with potent anti-inflammatory and anti-allergic effects in the airway. It inhibits 5-lipoxygenase and 12-lipoxygenase, reducing leukotriene synthesis relevant to asthma and COPD, and is documented in TCM respiratory formulas.

Baicalin, a flavone glucuronide from Baikal Skullcap (Scutellaria baicalensis), has preclinical evidence for attenuating NF-κB-mediated airway inflammation in asthma. Animal studies show it reduces ovalbumin-induced inflammation by inhibiting CCR7/CCL19/CCL21 signaling. It is a key constituent in TCM formulas used for respiratory conditions.

Baikal Skullcap (Scutellaria baicalensis) is a cornerstone TCM herb for lung heat and respiratory inflammation, containing baicalin and baicalein. Clinical studies of SCB-containing formulas show efficacy in asthma and respiratory infections; its flavones are among the most studied natural respiratory anti-inflammatories.

Balloon flower (Platycodon grandiflorus) root has 2,000+ years of use in East Asian medicine for cough, phlegm, bronchitis, and lung conditions. Its saponins provide expectorant and anti-inflammatory properties, with a 2025 PMC study confirming anti-asthmatic effects via TLR4/NF-κB inhibition in animal models.

Mixed tocopherol preparations containing delta and gamma-tocopherol reduce airway inflammation in human clinical trials. A gamma-tocopherol-enriched supplement (also containing delta-tocopherol) reduced sputum eosinophilia in asthma patients and prevented wood smoke-induced eosinophilic airway inflammation. Dietary intake of delta-tocopherol has been associated with reduced lung cancer risk in an epidemiological case-control study.

Beta-carotene has a well-characterized and clinically important relationship with lung health, primarily demonstrated through the ATBC and CARET trials showing high-dose supplementation (20–30 mg/day) significantly increased lung cancer incidence and total mortality in smokers and asbestos-exposed individuals. Early observational evidence had suggested a protective association between dietary beta-carotene and lung cancer risk, but RCT evidence reversed this expectation in high-risk populations.

Clinical studies show N. sativa seed (1–2 g/day) or oil (1 g/day) for 3–12 weeks significantly improved asthma symptoms and pulmonary function in adult patients. Reviews covering clinical evidence confirm bronchodilatory and lung-protective effects in obstructive pulmonary disease and sulfur mustard-exposed individuals.

Black seed (Nigella sativa) has been used in Islamic, Ayurvedic, and Egyptian traditional medicine for respiratory conditions for thousands of years. Multiple small RCTs show improvements in asthma symptoms and FEV1 with Nigella sativa oil. Its primary active compound thymoquinone has anti-inflammatory, bronchodilatory, and antioxidant properties.

Boswellia serrata (Indian Frankincense) has traditional Ayurvedic use for respiratory conditions and is supported by modern evidence in asthma. Clinical trials have shown boswellic acids reduce asthma symptoms and improve FEV1 through 5-lipoxygenase inhibition and reduction of leukotriene-mediated airway inflammation.

Boswellic acids, the active constituents of Boswellia serrata, inhibit 5-lipoxygenase to reduce leukotriene-mediated airway inflammation. Clinical evidence supports their use in asthma, with trials demonstrating improved FEV1 and reduced eosinophilia. They are also investigated for COPD and other inflammatory pulmonary conditions.

Sulforaphane from broccoli has been studied for lung cancer chemoprevention, and clinical trials in high-risk populations (former smokers) are ongoing. Sulforaphane's induction of phase II enzymes in lung tissue is documented in clinical samples. However, trials in neutrophilic airway inflammation showed mixed results.

Camellia sinensis (tea plant) produces green, white, oolong, and black tea, all containing catechins and polyphenols with documented lung health associations. Multiple epidemiological studies link Camellia sinensis consumption to reduced lung cancer risk and improved FEV1. Its EGCG and theaflavins reduce airway inflammatory cytokines.

The relationship between beta-carotene and lung health is clinically significant but paradoxical. While dietary beta-carotene from food is associated with lung health benefits and high fruit-and-vegetable diets reduce lung cancer risk, high-dose supplemental beta-carotene (20–30 mg/day) significantly increased lung cancer incidence and mortality in two large RCTs in smokers (ATBC and CARET). Vitamin A derived from beta-carotene is essential for lung development and mucosal defense.

Cineole (1,8-cineole, eucalyptol) is the primary bioactive terpenoid of eucalyptus oil with robust clinical evidence for COPD and asthma. RCTs have shown 1,8-cineole significantly reduces COPD exacerbation rates, improves FEV1, and allows steroid-sparing in asthma. It is approved by Commission E for upper respiratory tract catarrh.

Coleus forskohlii has a documented history of use in Ayurvedic medicine for respiratory and asthma conditions. Its active compound forskolin elevates cyclic AMP in bronchial smooth muscle, producing bronchodilation. A clinical study found inhaled forskolin powder improved FEV1 in asthma patients; another trial found oral forskolin non-inferior to inhaled beclomethasone for mild-to-moderate asthma.

Cordyceps (sinensis and militaris) has been used in Traditional Chinese and Tibetan medicine for centuries as a lung tonic. Modern preclinical and clinical studies indicate bioactive compounds—cordycepin, adenosine, and polysaccharides—can improve oxygen utilization, reduce airway inflammation, and support respiratory function. A 2025 PMC review documented its potential in managing air pollutant-related respiratory diseases.

Large prospective epidemiological studies associate high BCX intake with 15–40% reduced risk of lung cancer. BCX suppresses cigarette smoke-induced lung inflammation, oxidative DNA damage, and squamous metaplasia in animal models. Epidemiological evidence is supported by consistent inverse associations across multiple cohort studies.

Curcumin is the primary bioactive polyphenol of turmeric, with preclinical and clinical evidence for anti-inflammatory activity in asthma, COPD, and cystic fibrosis. It reduces airway inflammation via NF-κB inhibition, decreases eosinophils, and may correct CFTR protein folding in cystic fibrosis models.

Delta-tocopherol has been shown to be more active than α- or γ-tocopherol in inhibiting lung tumorigenesis in animal models. Dietary delta-tocopherol intake is inversely associated with lung cancer risk in epidemiological data. It exerts anti-inflammatory and antioxidant effects relevant to lung injury from environmental pollutants and oxidative stress.

Echinacea purpurea is the most studied Echinacea species for respiratory infections, with clinical trials showing reductions in cold and upper respiratory infection duration and severity. It is recognized by the German Commission E and NCCIH for supportive treatment of upper respiratory tract infections relevant to lung defense.

EGCG is the primary bioactive catechin of green tea with strong preclinical evidence for lung anti-inflammatory and antifibrotic effects. It inhibits NF-κB, reduces MMP-9-mediated tissue destruction in COPD emphysema models, and shows antiviral activity against respiratory pathogens. Epidemiological data supports association with lower lung cancer risk.

Elder (Sambucus nigra) flowers and berries have traditional use in European herbal medicine for respiratory infections, catarrh, and influenza. Clinical RCTs support elderberry's efficacy in reducing URI duration and severity. Commission E recognizes elder flower for colds and febrile conditions affecting the respiratory tract.

Elderberry (Sambucus nigra) has clinical evidence for reducing duration and severity of upper respiratory infections relevant to lung defense. A meta-analysis of RCTs found elderberry supplementation substantially reduced upper respiratory symptoms. Its flavonoids bind and inhibit viral surface proteins including influenza hemagglutinin.

Ephedra (ma huang, Ephedra sinica) contains ephedrine and is definitively effective as a bronchodilator for mild asthma, functioning as a sympathomimetic. It has been used in TCM for respiratory conditions for over 5,000 years. Its use is restricted in many countries due to cardiovascular safety concerns.

Eucalyptus (Eucalyptus globulus) and its volatile constituent cineole (1,8-cineole) have robust clinical evidence for respiratory conditions. 1,8-cineole demonstrated statistically significant improvements in lung function and exacerbation rates in COPD RCTs and is a recognized mucolytic and anti-inflammatory agent.

Forskohlii root (from Coleus forskohlii) contains the bronchodilatory compound forskolin that raises bronchial smooth muscle cAMP, producing airway relaxation. Ayurvedic tradition and modern pharmacological data both support its use for asthma and respiratory conditions.

Forsythia acts on the lung meridian in TCM and has substantial preclinical evidence for protecting lung tissue from acute injury and viral infection. Forsythoside A protects mice from LPS-induced acute lung injury. Studies also show efficacy against RSV-induced pneumonia and influenza in animal models. Combination formulas containing Forsythia have documented clinical use for lung infections in China.

Fritillary is among the best-studied TCM herbs for lung disease. Alkaloids demonstrate antitussive, expectorant, anti-inflammatory, and anti-fibrotic effects across multiple animal models including acute lung injury. The Chinese Pharmacopoeia lists lung-moistening as a primary indication. Fritillary preparations are used in clinical TCM settings for diverse pulmonary illnesses.

Gamma-tocopherol reduces allergen-, endotoxin-, ozone-, and wood smoke–induced airway inflammation in both preclinical and human models, acting via RNS scavenging and COX-2 inhibition. Childhood lung function studies suggest tocopherol isoform balance may influence lung development. Evidence is strongest for acute inflammatory challenges; long-term lung function outcomes are less studied.

Ganoderma lucidum (reishi) is a medicinal mushroom with 2,000+ years of TCM use as a lung tonic. Its triterpenoids inhibit histamine and leukotriene release; polysaccharides modulate immune responses in the airway. Preclinical evidence supports use in asthma and respiratory infection; it appears in clinical lung support formulations.

A large European cohort study found that consuming raw garlic at least twice weekly was associated with a 44% lower risk of lung cancer. Garlic's sulfur compounds modulate NF-κB and Th2 cytokine pathways relevant to airway inflammation and chronic respiratory conditions. Traditional use of garlic for respiratory ailments spans ancient Greek, Native American, and Asian medical traditions.

Allicin from garlic kills lung pathogenic bacteria including Streptococcus pneumoniae, Pseudomonas aeruginosa, and MDR Staphylococcus strains as both a vapor and in solution. Its volatile nature makes it biologically suitable for airway delivery. Traditional use for lung conditions is documented; clinical RCT evidence for lung disease is limited.

Ginger (Zingiber officinale) has been used in Ayurvedic, TCM, and other traditional systems for respiratory conditions. Preclinical studies show gingerols and shogaols relax airway smooth muscle and reduce airway inflammation. A clinical study found ginger supplementation improved lung function parameters in asthmatic patients.

Panax ginseng has been used in TCM for respiratory support and is the most commonly used traditional herb (32.5% usage frequency) in lung cancer treatment plans. Clinical and preclinical evidence shows ginsenosides reduce airway inflammation, improve exercise capacity in COPD, and modulate lung immune response.

Ginsenosides are the primary active triterpenoid saponins of Panax ginseng with documented anti-inflammatory effects in the airway and preclinical evidence for COPD and lung cancer. They reduce NF-κB-mediated cytokine production, inhibit airway remodeling, and are investigated in clinical studies for COPD and NSCLC.

G. littoralis is one of the primary TCM herbs for lung conditions and is formally listed in the Chinese Pharmacopoeia for treating lung heat, moistening lung dryness, and as an expectorant. Pharmacological studies confirm antitussive, anti-inflammatory, and lung-protective activities. A study on lung cancer cell migration has also been published.

Glycyrrhizin, the principal triterpene glycoside of licorice root, has documented anti-inflammatory, antiviral, and expectorant properties in the respiratory tract. Preclinical studies show it suppresses LPS-induced acute lung inflammation, and it has been investigated in Japanese clinics for viral respiratory infections and hepatitis.

Green tea (Camellia sinensis) catechins, particularly EGCG, have preclinical and epidemiological evidence for lung health. Population studies associate green tea consumption with reduced lung cancer risk and improved lung function. EGCG inhibits airway inflammatory pathways and has demonstrated antiviral activity against respiratory pathogens.

Hesperidin demonstrates protective effects against a range of inflammatory lung conditions including COPD, pulmonary fibrosis, ARDS, and COVID-19-related lung injury in preclinical models. It inhibits NF-κB, iNOS, and COX-2-driven airway inflammation and activates the ERK/Nrf2 antioxidant pathway in lung tissue. Human clinical evidence is limited; most data are from animal models.

Boswellia serrata demonstrates clinically documented benefits for lung function. In the landmark Gupta et al. (1998) asthma RCT, 70% of treated patients showed improvements in FEV1, FVC, and PEFR vs. 27% on placebo. The mechanism of 5-LOX inhibition is directly relevant to airway inflammation and bronchoconstriction.

I3C has been studied clinically as an adjunct treatment for recurrent respiratory papillomatosis (RRP), an HPV-driven condition causing papillomas of the larynx and airway. Phase I and prospective open-label clinical studies in 18–45 patients showed papilloma growth cessation or reduction in roughly one-third of treated patients. Preclinical studies also demonstrate inhibition of tobacco smoke carcinogen-induced lung adenocarcinoma in animal models.

Altered L-arginine/NO homeostasis is implicated in the pathogenesis of pulmonary hypertension (PH), bronchopulmonary dysplasia, asthma, and COPD. A human clinical trial in patients with idiopathic pulmonary arterial hypertension (IPAH) and Eisenmenger Syndrome found that L-citrulline malate reduced mean pulmonary artery pressure and improved 6-minute walk distance. Preclinical data in neonatal animal models further establish citrulline's structural and functional benefits in pulmonary vascular remodeling.

NAC (deacetylated in vivo to L-cysteine) is an established adjunct therapy for chronic lung diseases including COPD, bronchiectasis, and cystic fibrosis, via mucolytic, antioxidant, anti-inflammatory, and anti-biofilm actions. A 2026 evidence-based consensus document affirmed its clinical utility across multiple chronic respiratory conditions.

GSH is one of the most abundant antioxidants in human lung epithelial lining fluid and is critical for defending against oxidative lung damage. Several lung disorders are characterized by increased alveolar oxidant burden that depletes lung GSH. Low GSH levels are linked to abnormalities in lung surfactant and impaired antiprotease function in the epithelial lining fluid.

Licorice root (Glycyrrhiza glabra/uralensis) has been used in TCM, Ayurveda, and European herbalism for respiratory and lung conditions for millennia. Glycyrrhizin and isoliquiritigenin inhibit lung inflammation in preclinical studies; flavonoid extracts suppress LPS-induced acute pulmonary inflammation in mice. It is listed in COPD herbal reviews.

Limonene has demonstrated anti-inflammatory effects in the respiratory system in animal models, including attenuation of acute lung injury by reducing pro-inflammatory cytokines and inflammatory cell infiltration. Asthma models show limonene reduces eosinophils, IgE, and Th2 cytokines in bronchoalveolar lavage fluid. A systematic review found LMN effective in preventing and controlling respiratory injuries via its anti-inflammatory properties.

Luteolin has been extensively studied for its effects across multiple pulmonary conditions, including COPD, asthma, pneumonia, and acute lung injury. It suppresses multiple inflammatory signaling pathways in lung tissue. Evidence is largely preclinical with emerging mechanistic data.

Lycopene accumulates in lung tissue and a randomized trial demonstrated that supplementation reduced lung epithelial DNA damage by 20% following ozone challenge. A COPD pilot study found lycopene supplementation (20 mg/day, 4 months) reduced oxidative stress markers and inflammatory cytokines. Animal and cell studies further support protection against smoke-induced lung damage.

Malabar nut is one of the most extensively researched medicinal plants for lung health, with documented expectorant, bronchodilatory, anti-inflammatory, and mucoprotective properties. Multiple in vitro and animal studies, plus a clinical trial of a combination product, support its role in supporting respiratory and lung function.

Mullein (Verbascum thapsus) has been used in European and American folk medicine for centuries to treat respiratory conditions including coughs, bronchitis, and asthma. Its mucilage provides demulcent soothing of inflamed airways, while saponins act as expectorants. A 2021 PMC review confirmed anti-inflammatory phytochemicals, particularly quercetin, correlate with its respiratory uses.

NAC is one of the most extensively documented respiratory therapeutics, with clinical evidence for COPD, cystic fibrosis, chronic bronchitis, and idiopathic pulmonary fibrosis. It acts as a mucolytic, antioxidant, and anti-inflammatory agent, replenishing intracellular glutathione in the lung. High-dose NAC (600 mg twice daily) significantly reduced exacerbation frequency in stable COPD in RCT evidence.

Omega-3 fatty acids have documented anti-inflammatory effects on lung tissue. Epidemiological and mechanistic data suggest omega-3 intake may slow lung function decline and reduce airway inflammation. A Cochrane review found omega-3 supplements might improve lung function in cystic fibrosis patients.

Onion and its constituents exert bronchodilatory and anti-inflammatory effects on lung tissue. Quercetin and isoquercitrin reduce eosinophil counts and inflammatory cytokines in bronchoalveolar lavage fluid. Thiosulfinates in onion inhibit PAF-induced bronchial obstruction, and onion extract relaxes tracheal smooth muscle in a concentration-dependent manner.

Intramuscular vitamin A palmitate supplementation in very-low-birth-weight preterm infants has been shown in randomized controlled trials to significantly reduce the incidence of bronchopulmonary dysplasia (BPD). StatPearls (NCBI) confirms parenteral retinyl palmitate reduces BPD risk.

Palmitic acid is the structural building block of dipalmitoylphosphatidylcholine (DPPC), the principal component of pulmonary surfactant that reduces alveolar surface tension and prevents lung collapse during breathing. DPPC consists of two palmitic acid C16 chains, and its fully saturated structure is essential for effective surface tension reduction during exhalation. Palmitic acid also enhances surfactant surface activity and confers resistance to inhibition by blood proteins.

Perilla fruit water extract has been used in TCM for pulmonary diseases and was shown in animal models to reduce lung inflammation and neutrophil infiltration via MAPK/JNK-AP-1/c-Fos signaling. Perilla leaf extracts suppressed pro-allergic cytokines in human bronchial epithelial cells. TCM designates perilla as a primary herb for lung qi conditions.

Pine bark extract improves lung function in asthma patients (documented in clinical trials) and has traditional use for respiratory health across multiple cultures. Pycnogenol reduces airway inflammation via leukotriene and cytokine inhibition. Historically, pine steam and resin were used for lung conditions by Native Americans and ancient Greeks.

Plantago major has documented effects on lung function, including improvements in FEV1 and FVC in asthmatic patients in clinical studies. Animal models show P. major extract reduces airway inflammation and histopathological lung damage. Commission E endorses P. lanceolata for catarrh of the airways.

Platycodon grandiflorus (balloon flower root, jie geng) has been used in TCM and Korean herbal medicine for over 2,000 years to treat cough, phlegm, and bronchitis. Its saponins (platycodin D) demonstrate expectorant, anti-inflammatory, and immunomodulatory effects in vitro and in animal asthma models, including NF-κB pathway suppression.

Platycodon root (Platycodon grandiflorus, jie geng) is the pharmaceutical form of balloon flower root used in TCM for respiratory conditions. Its saponins provide expectorant, anti-inflammatory, and bronchodilatory effects supported by preclinical studies. A 2025 PMC study confirmed anti-inflammatory action in asthmatic models via TLR4/NF-κB suppression.

Quercetin is a plant flavonoid with potent antioxidant and anti-inflammatory properties investigated in COPD. A pilot Phase II RCT (14 COPD patients, 2000 mg/day, 6 months) found quercetin significantly reduced BAL IL-8, IL-1β, 8-isoprostane, and serum surfactant protein D compared to placebo. Epidemiological data links quercetin-rich diets to lower asthma incidence and reduced COPD severity.

Reishi (Ganoderma lucidum, lingzhi) has been used in TCM for respiratory conditions for over 2,000 years, classified as a 'lung tonic.' Preclinical studies show triterpenoids and polysaccharides reduce airway inflammation, inhibit histamine release, and provide antioxidant protection relevant to asthma and COPD. It is listed in respiratory support clinical formulas.

Resveratrol is a polyphenol stilbene with preclinical evidence for COPD and asthma. It activates SIRT1 in lung tissue, reducing cigarette smoke-induced NF-κB activation and oxidative stress. It is included in the Herbal Medicine for COPD review as a pharmacologically relevant compound.

Rosmarinic acid demonstrates lung-protective activity in preclinical models of acute lung injury, reducing NF-κB-driven pulmonary inflammation and oxidative stress. In a thermal injury systemic inflammation model, RA reduced multi-organ dysfunction markers including lung injury biomarkers. Preclinical evidence for asthma is supported by one human clinical trial for allergic airway disease.

SDG protects non-malignant lung cells from radiation-induced DNA damage, reduces oxidative lung injury, and decreases pulmonary inflammation and fibrosis in preclinical models. It upregulates antioxidant cytoprotective enzymes HO-1, GSTM1, and NQO1 in irradiated lung cells and improved clonogenic survival. Dietary flaxseed (the SDG source) ameliorated thoracic radiation damage in mice both pre- and post-exposure.

SPMs are constitutively biosynthesized in lung tissue and play essential roles in resolving acute lung inflammation and preventing progression to fibrosis. Reduced SPM levels have been measured in human lung lavage fluid in ARDS, COPD, and asthma. Supplementation with omega-3 precursors increases lung SPM levels in humans.

Stigmasterol reduced airway inflammation, mucus hypersecretion, and airway hyperresponsiveness in OVA-induced asthmatic mouse models via inhibition of TGF-β1/Smad2, IL-17A signaling, and the substance-P receptor (NK1-R). Anti-inflammatory and antioxidant effects in bronchial cells were also demonstrated in vitro.

Sulforaphane induces Nrf2-driven antioxidant responses in lung tissue, inhibits TLR-mediated inflammatory signaling in COPD macrophages, and protects against airborne carcinogen damage. Human trials show SFN enhances detoxification of lung-relevant pollutants and suppresses airway inflammatory mediators.

Aster tataricus extracts have been studied for acute lung injury and pulmonary fibrosis in preclinical models. Network pharmacology and animal experiments show that ATE inhibits inflammatory cytokine release and promotes vascular endothelial repair in LPS-induced acute lung injury. Research into pulmonary fibrosis is also ongoing. Traditional use for lung conditions spans over 2,000 years in TCM.

Thyme (Thymus vulgaris) is recognized by the EMA and Commission E as a medicinal herb for bronchitis and upper respiratory catarrh. Clinical studies show thyme extract with primrose root speeds recovery from bronchitis. Carvacrol and thymol, its main phenols, act as expectorants, antispasmodics, and antimicrobials in the respiratory tract.

Thymoquinone is the principal bioactive compound in Nigella sativa (black seed), with preclinical evidence for anti-inflammatory, antioxidant, and bronchodilatory effects in asthma and COPD models. Small clinical trials using Nigella sativa oil have reported improvements in asthma symptoms and lung function parameters.

Thymus vulgaris exerts clinically demonstrated spasmolytic, secretolytic, expectorant, and antimicrobial effects on the respiratory tract, with multiple RCTs showing benefit in acute cough conditions involving the lungs. Thymol directly modulates mucus secretion in respiratory epithelial cells and inhibits inflammatory mediators in lung tissue. EMA HMPC and German Commission E both recognise thyme preparations for respiratory indications.

A randomized crossover clinical study in 17 asthmatic adults found that tomato extract and tomato juice (45 mg lycopene/day each, 7 days) significantly reduced airway neutrophil influx and sputum neutrophil elastase activity versus placebo. These findings suggest lycopene may reduce airway inflammation in asthma.

Turmeric (Curcuma longa) contains curcumin, which modulates NF-κB inflammatory signaling relevant to asthma, COPD, and cystic fibrosis. Preclinical and some clinical evidence supports anti-inflammatory effects in airways. The PMC respiratory herbal review identifies curcumin for CFTR protein correction in cystic fibrosis.

Human studies in bronchial asthma patients demonstrated objective improvements in lung function parameters including FEV1, vital capacity, and peak expiratory flow rates following Tylophora administration. Eosinophil count reductions further reflect a favorable effect on pulmonary inflammatory status. These findings establish a scientific basis for Tylophora's benefit to lung function.

Vitamin A is essential for lung alveolar development, maintenance, and regeneration. Deficiency causes impaired alveologenesis and structural lung changes. A large Mendelian randomization study in 150,000 UK Biobank participants found a causal effect of carotene-form vitamin A on adult lung function (FVC). NHANES data associate higher vitamin A intake with better spirometric parameters.

PEITC from watercress inhibits metabolic activation of the major tobacco lung carcinogen NNK in humans—demonstrated in a clinical study in smokers. Cell line studies confirm PEITC suppresses non-small cell lung cancer cell growth and metastasis. Human epidemiological data supports inverse associations between cruciferous vegetable intake and lung cancer risk.

Adenophora (sha shen, Adenophora tetraphylla or stricta) is a TCM herb classified as nourishing lung Yin and relieving dry cough, chronic bronchitis, and tuberculosis-related lung conditions. It is used in Yin-nourishing respiratory formulas in Chinese medicine.

Agrimony is traditionally used in Central European folk medicine for pulmonary diseases and bronchitis, with infusions, tinctures, and gargles employed for respiratory conditions. Water extracts are described as used in treatment of airway diseases. No clinical trial in respiratory disease exists.

Bitter apricot kernel (xing ren) is one of the most frequently used herbs in TCM for lung health, appearing in classic formulas for cough, wheezing, and respiratory infections. Its use is documented from the Shennong Bencao Jing. TCM pharmacology attributes its effects to moistening the lungs and descending Lung Qi. Modern phytochemical analysis supports an antitussive mechanism via amygdalase and respiratory center stimulation.

Bamboo preparations are used in TCM for lung-heat disorders, respiratory infections, and lung detoxification. Succus Bambusae has 2,500 years of documented use in clearing lung heat and facilitating respiration. Indian traditional formulations containing bamboo are used for pneumonia, tuberculosis, and viral respiratory infections.

Traditional Indigenous and aromatherapy sources cite black spruce for lung conditions including coughs, asthma, and bronchitis. The essential oil constituents — particularly camphene and bornyl acetate — have mucolytic and anti-inflammatory properties relevant to lung health. Preclinical data on bornyl acetate supports anti-inflammatory action in lung tissue.

Chen Pi targets the Lung meridian in TCM and is traditionally used to clear phlegm, reduce cough, and support respiratory function. Its anti-inflammatory flavonoids and mucolytic volatile oils provide scientific plausibility, though direct human lung endpoint RCTs are lacking.

Codonopsis pilosula (dang shen) is used in TCM as a milder substitute for Panax ginseng to tonify the lungs and spleen. It is indicated in TCM for dry cough, shortness of breath, and lung qi deficiency, and appears in traditional respiratory formulas.

TCM assigns coix seed to the lung meridian and traditional texts document it for lung carbuncle (pulmonary abscess), pulmonary edema, wet pleurisy, and lobar pneumonia. Modern pharmacological research shows anti-inflammatory and possibly anti-cancer effects in lung cell lines.

Coltsfoot (Tussilago farfara) has been used in European and Asian traditional medicine for centuries for chronic cough, bronchitis, and respiratory congestion. Studies have confirmed antitussive, expectorant, and anti-inflammatory activities. It contains pyrrolizidine alkaloids (hepatotoxic) limiting its clinical use.

Echinacea has been used traditionally by Native Americans and in Western herbal medicine for respiratory infections and lung health. It is widely recognized by NCCIH as a traditional remedy for the common cold and upper respiratory infections, with some clinical evidence supporting reduction in duration and severity.

Elecampane (Inula helenium) has been used in European, Ayurvedic, and Chinese traditional medicine for respiratory conditions including asthma, bronchitis, whooping cough, tuberculosis, and pleurisy. Its active compounds inulin and alantolactone soothe bronchial passages and provide expectorant and antitussive action.

Horehound (Marrubium vulgare) has been used in European, North African, and American traditional medicine for respiratory complaints including cough and bronchitis. It is approved by the German Commission E for symptomatic relief of acute bronchitis and cough, classified as an expectorant and bronchosecretolytic herb.

Hyssop (Hyssopus officinalis) has been used in European and Middle Eastern traditional medicine since antiquity as an expectorant, antitussive, and antispasmodic for cough, bronchitis, and asthma. Its volatile oils (pinocamphone, isopinocamphone) are responsible for bronchospasmolytic activity.

Inula racemosa (pushkarmool) is used in Ayurvedic medicine as a respiratory tonic for bronchitis, asthma, and cough. It shares active sesquiterpene lactones with Inula helenium and is classified in Ayurveda as a bronchodilator and expectorant. It appears in TCM and Ayurvedic respiratory preparations.

Lily bulb's principal TCM indication is 'moistening the lungs', recorded since the Han dynasty. It is used for dry cough, hemoptysis, and lung yin deficiency across multiple traditional medical systems including TCM, Ayurveda, and Japanese Kampo. Modern pharmacological studies show anti-inflammatory effects in airway models and antitussive properties attributed to saponins, supporting but not fully validating the traditional use via human clinical trials.

Lobelia (Lobelia inflata) has been used in Native American and Western herbal medicine as a bronchodilator and expectorant for asthma, bronchitis, and respiratory congestion. The alkaloid lobeline acts as a respiratory stimulant, thins mucus, and relaxes smooth muscles. In the UK it is restricted to licensed herbal practitioners.

Lungwort (Pulmonaria officinalis) has been used in European herbal medicine since at least the 1600s for respiratory conditions, based initially on the Doctrine of Signatures (its spotted leaves resembling lung tissue). It contains mucilage, saponins, and rosmarinic acid that provide demulcent and antioxidant support to the airways.

Marshmallow root (Althaea officinalis) has been used in European traditional medicine since antiquity as a demulcent and expectorant for respiratory complaints including cough, bronchitis, and dry irritated airways. The EMA recognizes its use for soothing irritated mucous membranes in the respiratory tract.

Menthol oil activates TRPM8 cold-sensing receptors in the airways, producing decongestant and antitussive effects. It is an established pharmaceutical ingredient in respiratory products and is recognized by Commission E and ESCOP for upper respiratory catarrh. Traditional use across multiple cultures supports its respiratory application.

Asclepias tuberosa (pleurisy root) was one of the most prominent traditional remedies for lung diseases in North American herbal medicine, listed in the US Pharmacopeia from 1820 to 1905. It was used for pleurisy, pneumonia, consumption, and general pulmonary complaints by both Indigenous peoples and Eclectic physicians. No human clinical evidence of efficacy exists.

Morus alba root bark (Sang Bai Pi) is a core TCM herb for lung conditions including cough with heat phlegm, wheezing, and bronchial congestion. Mulberry leaves are used for lung heat with dry cough. These uses are listed in the Chinese Pharmacopoeia, with supporting anti-inflammatory and antibacterial preclinical data.

A. vulgaris has a traditional role as an expectorant and is used for bronchitis, colds, and respiratory complaints in European and Asian folk medicine. The constituent 1,8-cineole (eucalyptol) has documented mucolytic, broncholytic, and anti-inflammatory properties. No human clinical trials on mugwort for lung health exist.

TC is described in Ayurvedic tradition as supporting lung function and used for cough, dyspnea, asthma, and bronchitis. Classical Ayurvedic texts list lungs as one of the primary organ systems supported by TC. Modern evidence remains preclinical.

Myrrh is traditionally classified as an expectorant and anti-inflammatory agent for lung conditions including bronchitis, asthma, and chest infection. Myrrh essential oil used in chest rubs and inhalation to relieve lung congestion. The PMC pharmacological review confirms expectorant and anti-inflammatory use for chest ailments.

Ophiopogon japonicus (mai dong) is a TCM herb used to treat dry cough, lung dryness, and respiratory conditions by stimulating mucus production and soothing the airways. It is included in the Lung Support Formula studied in a Chinese clinical trial for improving respiratory symptoms in older adults.

Moistening the lungs is one of the three primary classical actions of ophiopogon root in TCM and Kampo medicine, used for lung yin deficiency, dry cough, and pulmonary conditions. The Chinese Pharmacopoeia, Shennong's Classic, and the Japanese Pharmacopoeia all record this indication. Preclinical evidence shows anti-inflammatory activity relevant to respiratory tissues.

Osha (Ligusticum porteri) is a Rocky Mountain herb historically used by Native American tribes for respiratory conditions including cough, bronchitis, and pneumonia. Its camphor-rich root is an expectorant and antiviral agent used in Western and Native American herbalism for lung support.

Pear is a cornerstone food in TCM for lung nourishment, described as clearing lung heat and moistening the respiratory tract. Nutritionally, pear provides vitamin C and antioxidants that may protect lung tissue from oxidative stress. A 2025 PubMed review of Asian pears identified lung-protective activity for pear polyphenols, though clinical trial data are absent.

Peppermint (Mentha x piperita) and its principal constituent menthol have documented use for respiratory complaints including cough, nasal congestion, and bronchitis. Menthol activates cold-sensing TRPM8 receptors in the airway, producing perceived decongestant and antitussive effects. Commission E recognizes it for upper respiratory catarrh.

P. kurroa is used in traditional Ayurvedic and Tibetan medicine for respiratory and lung disorders, including bronchitis and COPD-like presentations. The compound androsin is mechanistically active against PAF-induced lung inflammation. Clinical literature is limited to asthma-focused studies rather than lung health broadly.

Plantain has been traditionally used for lung-related ailments including asthma, emphysema, and bronchitis in multiple global traditions. Preclinical studies show anti-inflammatory effects in lung tissue. Traditional Chinese Medicine uses related Plantago asiatica for lung-moistening. Commission E recognizes P. lanceolata for respiratory catarrhs.

Yuan Zhi has been used in TCM and related Asian medical traditions for lung conditions including cough, phlegm accumulation, bronchial asthma, and acute lung injury. The Chinese Pharmacopoeia assigns it to the Lung meridian. Preclinical studies show anti-inflammatory effects in lung injury models, but human lung-health trials are lacking.

Polygala root is listed in the Chinese Pharmacopoeia with Lung meridian affinity and has centuries of documented use as an expectorant for lung-related conditions. Preclinical studies show it suppresses acute lung injury via anti-inflammatory mechanisms and supports lung epithelial health.

TCM uses pomelo peel (Huajuhong) specifically to tonify and regulate lung Qi, clear phlegm, and relieve respiratory complaints. Naringenin has been studied in vitro for anti-proliferative effects in lung cancer cell lines. Pomelo leaf essential oil exhibits 5-lipoxygenase inhibition activity relevant to airway inflammation.

Quillaja bark's traditional use by Andean peoples for chest complaints encompasses general lung support via expectorant action. The saponins promote more fluid airway secretions to aid clearance. No clinical trials address lung function or lung health outcomes.

Red clover has a well-documented traditional use for lung health, particularly for respiratory conditions such as whooping cough, bronchitis, and asthma. Traditional Chinese Medicine used it as a cough suppressant and antitussive agent. No clinical trial evidence specifically for lung health exists.

In TCM, schisandra is classified as a primary 'astringing' herb that inhibits leakage of Lung qi and is specifically indicated for chronic coughs, wheezing, and dyspnea, particularly from weakened Lung and Kidney organ systems. It is listed in the Shennong Bencao Jing for coughs. Modern pharmacological studies confirm antitussive and antiasthmatic properties. Clinical trials specifically for lung health have not been conducted.

Schisandrins are the bioactive lignan constituents of Schisandra chinensis (wu wei zi), a TCM herb used to 'astrnge the lungs' and relieve chronic cough and asthma. Preclinical studies show schisandrins reduce oxidative stress and inflammatory mediators in lung tissue.

Schizandrol A is a lignan from Schisandra chinensis used in TCM for chronic cough, asthma, and lung Qi deficiency. Preclinical studies show it reduces lung oxidative stress and inflammatory cytokines relevant to respiratory conditions, and it is a constituent of TCM formulas clinically studied for COPD.

Slippery elm (Ulmus rubra) inner bark has been used by Native Americans and in Western herbal medicine as a demulcent for soothing irritated respiratory mucous membranes. The inner bark's mucilage forms a protective gel that calms inflamed throat and airway tissue, making it useful for cough and bronchitis.

Slippery elm bark (Ulmus rubra) is the dried inner bark used as a demulcent for respiratory mucous membrane soothing. It is recognized by the FDA as a safe OTC demulcent and has traditional use in treating cough and airway irritation. Its mucilage content provides protective coating to inflamed airway tissue.

Solomon's seal is a primary lung tonic in TCM, listed in the Chinese Pharmacopoeia for dry coughs and lung dryness conditions. It is described as moistening and nourishing the lungs, with expectorant and demulcent actions. A PMC animal study (2023) investigated P. odoratum polysaccharides in lung injury models.

Spruce pitch, needles, and inner bark were traditionally used internally by multiple indigenous peoples for lung congestion and chest complaints. Topical chest rubs made from resin ointment were also used to relieve lung congestion. Decoctions of bark have been documented for respiratory complaints including historical use for tuberculosis.

In TCM, Trichosanthes fruit is the primary herb for 'clearing and draining lung heat,' transforming phlegm-heat, and moistening lung dryness. It is attributed to the lung meridian and is indicated for lung abscesses, pulmonary heart disease, and lung heat coughs. A murine study (2025) showed T. kirilowii fruit extract reduced airway inflammation and hyperresponsiveness but human evidence is limited.