Lungwort (Pulmonaria officinalis L.): A Comprehensive Reference
1. Identity and Botanical Classification
1.1 Nomenclature and Taxonomy
Pulmonaria officinalis, known by the common names lungwort, common lungwort, Mary's tears, and Our Lady's milk drops, is a herbaceous rhizomatous evergreen perennial plant of the genus Pulmonaria, belonging to the family Boraginaceae. The pharmacopoeial designation for the dried aerial parts is Pulmonariae Herba.
The genus name comes from the Latin pulmo, meaning lung, and was first used by Leonhart Fuchs (1501–1566), a German physician and one of the three founding fathers of botany. The species was named officinalis by Carl Linnaeus for the medical properties of these plants, used since the Middle Ages to treat coughs and diseases of the chest, because of the doctrine of signatures, whereby Christian doctors believed that plants that resemble any body part could be used to treat illnesses in that part, since God had put his signature in the plant to guide mankind.
The genus Pulmonaria, commonly known as lungwort, belongs to the Boraginaceae family and comprises around 18 species of perennial flowering plants. Pulmonaria officinalis L. (lungwort), belonging to the Boraginaceae family, is a herbaceous perennial plant, widely spread in Europe and western Asia.
1.2 Botanical Description
Lungwort is a low-growing plant, typically reaching 10–12 inches in height, with distinctive oval leaves that are covered in white or light-green spots. The leaves are ovate to lanceolate and can reach lengths of up to 8 inches (20 cm). They are often covered with a distinct pattern of white or silver spots, particularly prominent on younger leaves. During early spring, clusters of tiny trumpet-shaped flowers emerge, initially appearing in shades of pink and then maturing to blue or violet hues.
The plant is in flower from March to May, and the seeds ripen from May to June. The species is hermaphrodite (has both male and female organs) and is pollinated by bees and flies.
1.3 Disambiguation: Lungwort vs. Tree Lungwort
A critical point of identity is the distinction between two organisms that share the common name "lungwort." Lungwort (Pulmonaria officinalis) should not be confused with lungmoss (Lobaria pulmonaria), a type of lichen that sometimes shares the common name "lungwort." These are completely different organisms, though both have traditional respiratory uses.
Lobaria pulmonaria is a large epiphytic lichen consisting of an ascomycete fungus and a green algal partner living together in a symbiotic relationship with a cyanobacterium — a symbiosis involving members of three kingdoms of organisms. Commonly known by various names like tree lungwort, lung lichen, lung moss, and oak lungwort, it is sensitive to air pollution and is also harmed by habitat loss and changes in forestry practices. Tree lungwort (Lobaria pulmonaria) is a lichen that, because of its physical resemblance to the lungs, was once used to treat tuberculosis, pneumonia, and other lung diseases. The remainder of this article concerns exclusively Pulmonaria officinalis, the herbaceous flowering plant.
1.4 Common Names and Synonyms
Synonyms and common names found in the historical and contemporary literature include: Coucou Bleu, Dage of Jerusalem, Grande Pulmonaire, Herbe Cardiaque, Herbe au Cœur, Herbe aux Poumons, Lungenkraut (German), Pulmonaire, Pulmonaire Officinale (French), Pulmonaria, and Sauge de Jérusalem. The herbal drug is also referred to as Pulmonariae Herba in pharmacopoeial contexts.
1.5 Common Forms and Preparations
Several commercial products from lungwort (P. officinalis) are available on the market, such as mother tincture, leaves, dried aerial parts (commercially available as Pulmonaria herba), ingredients of various dietary supplements, as tea, and as cosmetics. The parts that grow above the ground are the parts used to make medicine. In contemporary medicine, Pulmonariae Herba is primarily used to alleviate pulmonary disorders, as an expectorant, anti-inflammatory, and mucilaginous drug. Externally, lungwort is applied to heal burns, wounds, cuts, and eczema.
2. Traditional and Historical Use
2.1 The Doctrine of Signatures and Medieval Origins
Lungwort has been used as an herbal remedy dating all the way back to the Middle Ages. It was at this time that the plant was named "lungwort" because of its leaves' resemblance to a diseased lung. In accordance with the Doctrine of Signatures, lungwort was once believed by medieval herbalists to be an effective remedy for treating lung diseases because the spotted plant leaves purportedly resembled diseased lung tissue.
Back in the Middle Ages, herbalists believed that you could tell the medicinal properties of a plant based on things like a leaf's shape. At that point, most of the herbal writers were monks, and it was commonly thought that God made plants for human use alone, and their appearance was a gift to humans to help them decode his methods.
2.2 Respiratory and Pulmonary Applications
Pulmonaria officinalis L., belonging to the Boraginaceae family, is a herbaceous perennial plant widely spread in Europe and western Asia. It has a long tradition of use in folk medicine of many countries as a remedy against various respiratory diseases including asthma, chronic bronchitis, tuberculosis, laryngitis, and coughs. It also has expectorant, antitussive, and diaphoretic properties.
The common name of Pulmonaria, i.e., "lungwort," derives from its traditional medicine recommendations such as the treatment of disorders related to the pulmonary system (e.g., bronchitis, cold, cough, laryngitis, and sore throat). Furthermore, data from numerous ethnomedicinal studies indicate that infusions and decoctions based on these plants may also be useful in the treatment of other complaints.
2.3 Digestive and Urinary Applications
Herbalists that incorporate the plant into their practices typically employ lungwort in internal preparations to treat stomach and intestinal issues, breathing ailments, coughs, colds, and kidney and urinary tract issues. People take lungwort to treat breathing conditions, stomach and intestinal ailments, and kidney and urinary tract problems. Lungwort is also used in cough medicines, to relieve fluid retention, and to treat lung diseases such as tuberculosis.
2.4 External and Topical Use
In contemporary medicine, Pulmonariae Herba is primarily used to alleviate pulmonary disorders, as an expectorant, anti-inflammatory, and mucilaginous drug. Externally, lungwort is applied to heal burns, wounds, cuts, and eczema. Traditional topical preparations typically involved fresh or dried leaf material applied as a poultice to affected skin areas.
2.5 Geographic and Cultural Distribution of Traditional Use
Lungwort (Pulmonaria officinalis L., Boraginaceae) is considered to possess therapeutic properties and it has been traditionally used as a remedy against various lung disorders in many countries. Native to Europe and Western Asia and now naturalized across parts of North America, lungwort caught the attention of early herbalists who followed the Doctrine of Signatures and believed the plant's resemblance to lung tissue was nature's way of signaling its purpose. Modern herbalists don't rely on that logic, but the tradition it inspired has proven remarkably persistent: lungwort benefits for respiratory comfort have kept it in continuous use across herbal medicine for over 500 years.
It has been used for medicinal purposes since ancient times due to the Doctrine of Signatures. Lungwort has been used in folk medicine for various purposes, including treating pulmonary diseases, and its leaves and flowers have also been used as food.
3. Phytochemical Profile: Key Constituents and Active Compounds
3.1 Overview of Phytochemical Complexity
More than 90 phytochemicals belonging to pharmacologically active phytochemical classes have been reported for lungworts, which can be considered as one of the important contributors to the biological properties along with micronutrients. However, safety studies and clinical trials are missing for lungworts to establish most of their potential biological properties.
Only fragmentary research has been done regarding the chemical constituents of Pulmonaria species. Consequently, the phytochemical profile of P. officinalis remains mostly unknown, particularly regarding phenolic compounds, for which only a very few publications are available.
3.2 Phenolic Acids and Their Derivatives
Phenolic acids — especially rosmarinic acid and its congeners — represent the most extensively characterized fraction of P. officinalis. Based on HPLC analysis, Neagu et al. reported that rosmarinic acid was the main constituent of both aqueous and ethanolic extracts obtained from P. officinalis; moreover, small amounts of rutin, hyperoside, chlorogenic, and caffeic acids were also detected.
Nine previously undescribed and 36 known phenolic compounds were detected in the 50% methanolic extract. Following multistep preparative procedures, structures of newly discovered compounds were determined using one- and two-dimensional techniques of NMR spectroscopy. Among the identified compounds were caffeic acid esters with aliphatic hydroxycarboxylic acids, conjugates of dicaffeic acid with rosmarinic acid, and previously unknown isomers of isosalvianolic acid A and yunnaneic acid E, as well as other lignans.
The dominant compounds identified were conjugates of danshensu with caffeic acid, i.e., rosmarinic, lithospermic, salvianolic, monardic, shimobashiric, and yunnaneic acids.
One particularly notable discovery was that P. officinalis extract contains yunnaneic acid B — a unique molecule that had been isolated so far only from Salvia yunnanensis — and also confirmed the presence of large amounts of rosmarinic acid.
Additional compounds detected include esters of caffeic acid with threonic and glyceric acid, lignans such as globoidnans A and B, a megastigmane glucoside, a few flavonol glycosides including kaempferol and quercetin derivatives (which were also present in malonylated forms), as well as a nitrile glucoside menisdaurin, and the tryptophan derivative lycoperodine-1.
3.3 Flavonoids
Brantner and Karting, based on thin-layer chromatography (TLC) identification, reported on the presence of quercetin and kaempferol glycosides. A fingerprint of methanol extract of P. officinalis obtained using micro-two-dimensional TLC indicated the presence of chlorogenic acid, myricetin, acacetin, glycosides of apigenin, quercetin (rutin and hyperoside), hesperetin (hesperidin), and naringenin (naringin).
3.4 Mucilages and Polysaccharides
Lungwort has a high mucilage content and this makes it useful in the treatment of chest conditions, being of particular benefit in cases of chronic bronchitis. Lungwort's high mucilage content is the basis for its traditional use in soothing irritated throat and airway tissue. When consumed as a tea or tincture, the mucilage forms a protective layer over irritated membranes, which may temporarily reduce discomfort.
3.5 Allantoin
In comparative studies, several compounds including allantoin, p-hydroxybenzoic acid, rutin, hydrocaffeic acid, rosmarinic acid, chlorogenic acid, and shikonin were extracted and quantified from shoot and root extracts of Boraginaceae plants including P. mollis and P. obscura. Allantoin and rosmarinic acid were found in extracts of both shoots and roots of P. obscura. While p-hydroxybenzoic acid and chlorogenic acid were absent in the root extract, they were present in the shoot extract, while allantoin and rosmarinic acid were found in both shoot and root extracts of P. mollis.
3.6 Tannins, Saponins, and Other Constituents
The main constituents of lungwort also include mucilages, saponins, tannins, and resins. Chemical analysis of a 70% ethanolic extract showed that the extract is rich in polyphenolics and that phytol is the most abundant compound, accompanied by terpenoids, fatty acids, alcohols, polyketides, and alkaloids.
3.7 Pyrrolizidine Alkaloids
The Boraginaceae family is known for the presence of pyrrolizidine alkaloids (PA), which can result in intoxication when present in herbal drugs. In one study, PAs were analyzed in the leaves, roots, rhizomes, and inflorescences of P. obscura using gas chromatography–mass spectrometry.
Leaves, roots and rhizomes, and inflorescences of Pulmonaria obscura from two localities were analyzed by GC-MS for their content in pyrrolizidine alkaloids. In roots and rhizomes, PAs of the lycopsamine type typical for the Boraginaceae could be detected, e.g., intermedine, lycopsamine, and their O(7)-derivatives. The total PA concentrations in roots and rhizomes lay between 0.026 and 0.158 mg/g dry weight. In leaves and inflorescences, on the other hand, only trace amounts of PAs (below 0.4 ng/mg dry weight) could be detected. No significant differences in total concentration of PAs could be found between the two sites.
Many pyrrolizidine alkaloids have been shown to be isolated from leaves, roots, and rhizomes of the lungwort species (Pulmonaria spp.). In both Pulmonaria officinalis and Pulmonaria obscura, such alkaloids as intermedine, lycopsamine, and symphitine have been detected. This means that P. officinalis is not an exception among Boraginaceae in not having pyrrolizidine alkaloids, as had been previously claimed.
3.8 Seasonal Variation in Metabolite Profiles
The phytochemical composition of lungwort is not static. Concentrations of all identified phenolic derivatives in the investigated herbal material were estimated using a method based on liquid chromatography with high-resolution mass spectrometry detection. Seasonal changes in the concentration of metabolites were also investigated using targeted and untargeted metabolomics techniques. Research from the 2018 PMC study found that rosmarinic acid and numerous other phenolic acid derivatives tend to accumulate in aerial parts in autumn, with simpler compounds such as caffeic acid and danshensu also showing increased levels.
4. Proposed Mechanisms of Action
4.1 Demulcent and Mucilaginous Activity
The mucilage fraction of lungwort is considered the primary driver of its traditional demulcent activity. When consumed as a tea or tincture, the mucilage forms a protective layer over irritated membranes, which may temporarily reduce discomfort. This mechanism is consistent with the pharmacology of other mucilage-rich herbs in the Boraginaceae and related families.
4.2 Antioxidant Mechanisms
Extracts at concentrations of 1–100 µg/mL partly prevented harmful effects of peroxynitrite-induced oxidative stress in blood plasma, decreasing oxidative damage to blood plasma components and improving its non-enzymatic antioxidant capacity. Notable antioxidant capacity was detected across all antioxidant tests applied in a 2025 study of the 70% ethanolic extract, including DPPH, PFRAP, total antioxidant capacity, and ferrous ion chelating assays.
4.3 Anti-Inflammatory Mechanisms (COX-2 Inhibition)
COX-2 inhibitor screening evidently suggested a stronger activity of P. officinalis (IC₅₀ of 13.28 and 7.24 µg/mL, in reaction with synthetic chromogen and physiological substrate (arachidonic acid), respectively). In silico studies on interactions of main components of the Pulmonaria extracts with the COX-2 demonstrated the abilities of ten compounds to bind with the enzyme, including rosmarinic acid, menisdaurin, globoidnan A, and salvianolic acid H.
4.4 Acetylcholinesterase Inhibition
Recent studies by Neagu et al. provided data on acetylcholinesterase and tyrosinase inhibitory actions of aqueous and ethanolic extracts obtained from P. officinalis. The anti-inflammatory activity of lungwort can also result in positive outcomes in different diseases. The acetylcholinesterase inhibition potential of lungwort extracts may be useful in the treatment of neurodegenerative disorders.
4.5 Genotoxic and Antigenotoxic Dose-Dependent Effects
The 70% ethanolic extract reduced cell viability only at the highest concentration tested (33.7%). Furthermore, a dual dose-dependent effect was recorded: a genotoxic effect of the tested extract was observed at higher concentrations, while non-genotoxic concentrations showed protective effects against oxidative damage of DNA. Specifically, pretreatment with lungwort extract reduced the DNA damage induced by Hâ‚‚Oâ‚‚, with the highest protective effect at the lowest tested concentration, indicating a hormetic mode of action.
5. Scientific Evidence by Area of Use
5.1 Respiratory System — Coughs, Bronchitis, and Mucosal Support
Traditional basis: P. officinalis has a long tradition of use in folk medicine of many countries as a remedy against various respiratory diseases including asthma, chronic bronchitis, tuberculosis, laryngitis, and coughs. It also has expectorant, antitussive, and diaphoretic properties.
Mechanistic plausibility: Preclinical research supports the plausibility of these mechanisms — recent in vitro studies (2021) on Pulmonaria officinalis extracts found measurable protection against peroxynitrite-induced damage in plasma and demonstrated COX-2 inhibitory activity, suggesting anti-inflammatory potential relevant to respiratory tissue.
Clinical evidence: No controlled human clinical trials specifically on lungwort for respiratory outcomes have been conducted. The evidence base for respiratory indications remains grounded in centuries of ethnomedicinal use and in vitro pharmacology, not controlled human trials. Evidence strength for this area is therefore preliminary.
5.2 Antioxidant Activity
In one published study, several investigations and tests were performed to determine the antioxidant activity and the acetylcholinesterase and tyrosinase inhibitory potential of Pulmonaria officinalis and Centarium umbellatum aqueous extracts (10% mass) and ethanolic extracts (10% mass and 70% ethanol). For each type of prepared extract of P. officinalis, the content of biologically active compounds — polyphenols, flavones, and proanthocyanidins — was determined. The antioxidant activity was assessed using two methods, namely the DPPH assay and reducing power assay.
A 2025 study concluded that these results provide a solid foundation for future research into this medicinal plant, with the aim of its potential therapeutic use in the prevention of diseases associated with oxidative stress. All antioxidant evidence to date is from in vitro or cell-based assays. No human trials have been conducted. Evidence strength: in vitro only; preliminary.
5.3 Anti-Inflammatory Activity
One PMC-indexed study described itself as "the first study on biological properties of P. obscura and P. officinalis, covering their activities in human blood plasma under the peroxynitrite-induced oxidative stress, verification of cellular safety, and preliminary evaluation of anti-inflammatory potential (based on the COX-2 inhibitory tests)."
The cellular safety of the extracts was confirmed in experimental models of blood platelets and peripheral blood mononuclear cells. COX-2 inhibitor screening evidently suggested a stronger activity of P. officinalis (IC₅₀ of 13.28 and 7.24 µg/mL, in reaction with synthetic chromogen and physiological substrate (arachidonic acid), respectively). In silico studies on interactions of main components of the Pulmonaria extracts with the COX-2 demonstrated the abilities of ten compounds to bind with the enzyme, including rosmarinic acid, menisdaurin, globoidnan A, and salvianolic acid H.
In vivo experiments are lacking in terms of exploring important biological properties such as anti-inflammatory and anti-neurodegenerative activity. Evidence strength: in vitro and in silico only; preliminary.
5.4 Neurodegenerative Disease Relevance
Acetylcholinesterase (AChE) and toll-like receptor 4 (TLR4) inhibitions are used in neurodegenerative disorder treatment strategies, including Alzheimer's disease (AD). Pulmonaria officinalis has demonstrated in vitro antioxidant, anti-inflammatory, and AChE inhibition. One study aimed to characterize the metabolomic profile and antioxidant activities of different P. officinalis fractions, specifically butanol and ethyl acetate fractions, using colorimetric, spectrophotometric, and chromatographic methods, and additionally studied their neuroprotective effect in lipopolysaccharide (LPS)-triggered Alzheimer's in mice.
No human clinical data exist for this indication. Evidence strength: in vitro and animal model only; very preliminary.
5.5 Skin Whitening and Tyrosinase Inhibition
The potential biological activities of lungworts include skin whitening properties, which have been observed in different studies. Tyrosinase is the rate-limiting enzyme in melanin synthesis, and its inhibition is a recognized mechanism underlying depigmenting cosmetic ingredients. Lungwort's tyrosinase inhibitory potential has been documented in in vitro settings. Evidence strength: in vitro only; cosmetic application remains investigational.
5.6 Wound Healing and External Applications
The potential biological activities of lungworts include wound-healing properties, which have been observed in different studies. In contemporary medicine, Pulmonariae Herba is primarily used externally to heal burns, wounds, cuts, and eczema. More animal studies are recommended to corroborate the antioxidant, anticoagulant, anti-convulsant, and wound-healing properties of lungworts. Evidence strength: traditional use and in vitro data only; no controlled human trials.
5.7 Antibacterial Properties
Antibacterial properties have been observed among the potential biological activities of lungworts in different studies. More than 90 phytochemicals belonging to pharmacologically active phytochemical classes have been reported for lungworts. No clinical-grade antimicrobial trials have been conducted on P. officinalis preparations. Evidence strength: in vitro only; preliminary.
5.8 Overall State of Clinical Evidence
Safety studies and clinical trials are missing for lungworts to establish most of their potential biological properties. Similarly, in vivo studies are lacking for anti-inflammatory and anti-neurodegenerative disorders, and more in vivo studies are required to strengthen the knowledge of their antioxidant, anticoagulant, and anti-convulsant properties. Despite the presence of Pulmonaria species in ethnomedicine and their use for culinary purposes, the biological activity of lungwort-based preparations and extracts from these plants is still poorly recognized. Moreover, there is a lack of comparative studies assessing the bioactive properties of different species from the Pulmonaria genus. Most of the available evidence derives from strictly chemical assays, mostly based only on DPPH or ABTS radical scavenging assays.
6. Body Systems Associated with Lungwort
- Respiratory system: Long traditional use as a folk remedy against various respiratory diseases including asthma, chronic bronchitis, tuberculosis, laryngitis, and coughs.
- Gastrointestinal system: Lungwort is taken to treat stomach and intestinal ailments.
- Urinary/renal system: Traditional use includes treating kidney and urinary tract issues.
- Integumentary system (skin): Externally, lungwort is applied to heal burns, wounds, cuts, and eczema.
- Nervous system: The acetylcholinesterase inhibition potential of lungwort extracts may be useful in the treatment of neurodegenerative disorders, though this remains at the in vitro stage.
- Immune/inflammatory pathways: COX-2 inhibitor screening evidently suggested activity of P. officinalis in preclinical in vitro models.
7. Dosage Forms and Reported Preparations
No regulated or pharmacopoeially standardized dosage has been established through clinical trials for P. officinalis. The dosages described below are drawn directly from the historical/ethnomedicinal and available source literature.
7.1 Herbal Tea (Infusion)
The most common traditional preparation is a hot-water infusion of the dried aerial parts. Traditional preparations involved steeping 1.5–2 g of dried leaves in 200 ml hot water for 10–15 minutes, straining, and drinking up to three times daily. In research, the total amount of phenols in the herbal tea was measured at 673.39 ±9.92 µM quercetin equivalents for P. officinalis.
7.2 Tinctures and Liquid Extracts
Commercially, lungwort is available as a mother tincture and as an ingredient of various dietary supplements. Tinctures are typically prepared from the aerial parts (leaves, stems) rather than the roots, consistent with the finding that PA concentrations are considerably lower in aerial parts than in root material.
7.3 Dried Aerial Parts (Pulmonaria herba)
The pharmacopoeial drug form is the dried aerial herb. Dried aerial parts are commercially available as Pulmonaria herba.
7.4 Research Extract Concentrations
In the key in vitro studies reviewed, the following concentrations were used: extracts at 1–100 µg/mL were tested in blood plasma models of peroxynitrite-induced oxidative stress. COX-2 inhibitory IC₅₀ values were 13.28 and 7.24 µg/mL (using synthetic chromogen and arachidonic acid as substrate, respectively) for P. officinalis fractions.
8. Safety Considerations and Interactions
8.1 Pyrrolizidine Alkaloid Content and Hepatotoxicity Risk
The most substantiated and scientifically grounded safety concern for lungwort — as with all Boraginaceae herbs — relates to the presence of pyrrolizidine alkaloids (PAs). Pyrrolizidine alkaloids are widely present in about three percent of flowering plants belonging to twelve different families. Boraginaceae, Asteraceae, and Fabaceae contain the most toxic PAs. To date, over 660 PAs have been identified in over 6,000 plant species, and about half of them are hepatotoxic.
Pyrrolizidine alkaloids are common secondary plant compounds with hepatotoxicity. The consumption of herbal medicines and herbal teas containing PAs is one of the main causes of hepatic sinusoidal obstruction syndrome (HSOS), a potentially life-threatening condition.
PAs exhibit developmental toxicity and have been shown to be hepatotoxic, pneumotoxic, genotoxic, and carcinogenic.
Concerning Pulmonaria specifically: many pyrrolizidine alkaloids have been shown to be isolated from leaves, roots, and rhizomes of the lungwort species (Pulmonaria spp.). In both Pulmonaria officinalis and Pulmonaria obscura, such alkaloids as intermedine, lycopsamine, and symphitine have been detected.
However, the concentration is strongly plant-part-dependent: the total PA concentrations in roots and rhizomes of P. obscura lay between 0.026 and 0.158 mg/g dry weight, while in leaves and inflorescences, only trace amounts of PAs (below 0.4 ng/mg dry weight) could be detected. The levels in Pulmonaria officinalis aerial parts (leaves) are generally considered to be very low to trace — often undetectable or negligible in recent analytical studies — compared to high-PA plants like comfrey root. PA concentrations tend to be higher in roots than in leaves across the Boraginaceae family.
PAs require metabolic activation in the liver to exert toxicity. Mediated by hepatic cytochrome P450 (CYPs), three toxic types (retronecine-type, heliotridine-type, and otonecine-type) of PAs generate reactive metabolites, dehydropyrrolizidine alkaloids (DHPAs), which form adducts with proteins and cause dysfunction of critical proteins, thus damaging hepatic sinusoidal endothelial cells and leading to hepatotoxicity.
8.2 Dose-Dependent Genotoxicity Signal
A 2025 in vitro study identified a dose-dependent genotoxic and antigenotoxic duality: a genotoxic effect of the tested extract was observed at higher concentrations, while non-genotoxic concentrations showed protective effects against oxidative damage of DNA. Pretreatment with lungwort extract reduced the DNA damage induced by Hâ‚‚Oâ‚‚, with the highest protective effect at the lowest tested concentration, indicating a hormetic mode of action. This finding was made on fetal fibroblast cells (MRC-5) in vitro and has not been assessed in humans.
8.3 Family-Level Allergy Considerations
As a member of the Boraginaceae family, which includes other well-known botanical allergens, individuals with known sensitivity to plants in this family (which includes borage and forget-me-nots) should exercise caution. Documented cases of allergic reactions specifically to P. officinalis are not prominently reported in the peer-reviewed literature reviewed here.
8.4 Potential Interactions
No controlled pharmacokinetic or pharmacodynamic interaction studies have been conducted for lungwort preparations in humans. The theoretical basis for interactions derives from constituent pharmacology: rosmarinic acid and related polyphenols identified as COX-2 binders in silico may theoretically interact with anti-inflammatory medications, and the high polyphenol load might theoretically influence anticoagulant activity, though no human evidence currently supports or refutes these hypothetical interactions.
8.5 Absence of Formal Regulatory Approval
Safety studies and clinical trials are missing for lungworts to establish most of their potential biological properties. Safety studies and clinical trials are also proposed to establish the potential biological properties of lungworts. No formal approval, established daily intake, or maximum residue limit has been set by the EMA, EFSA, or equivalent regulatory body specifically for P. officinalis preparations at the time of this writing, based on the sources reviewed.
Summary of Evidence Strength
- Traditional/ethnomedicinal use: Well documented across European folk medicine spanning at least five centuries, primarily for respiratory conditions.
- Phytochemistry: Moderately characterized; dominated by phenolic acids (especially rosmarinic acid), flavonoid glycosides, and mucilages, with a growing catalog of novel polyphenolic dimers and oligomers. Only fragmentary research has been done regarding the chemical constituents of Pulmonaria species.
- Biological activity: Demonstrated in vitro for antioxidant, anti-inflammatory (COX-2 inhibition), acetylcholinesterase inhibition, and protective effects on blood plasma. All findings are preclinical.
- Clinical evidence: Absent. Safety studies and clinical trials are missing for lungworts to establish most of their potential biological properties.
- Safety: PA content is plant-part-dependent and substantially lower in leaves than in roots; the specific risk profile for aerial-part preparations used at traditional doses has not been formally quantified in humans.
References
- Krzyżanowska-Kowalczyk J et al. (2018). Novel Phenolic Constituents of Pulmonaria officinalis L. LC-MS/MS Comparison of Spring and Autumn Metabolite Profiles. Molecules, 23(9), 2277. PMC6225171.
- Kolodziejczyk-Czepas J et al. (2021). Pulmonaria obscura and Pulmonaria officinalis Extracts as Mitigators of Peroxynitrite-Induced Oxidative Stress and Cyclooxygenase-2 Inhibitors – In Vitro and In Silico Studies. PMC7865227.
- Ignjatijević A et al. (2025). Assessment of Antioxidant Activity and Dose-Dependent Effect on Genotoxicity/Antigenotoxicity of Pulmonaria officinalis Ethanolic Extract. Pharmaceutics, 17(9), 1134. PMC12473312.
- Biological Activities and Phytochemicals of Lungworts (Genus Pulmonaria) Focusing on Pulmonaria officinalis. Applied Sciences, 12, 6678 (2022). ResearchGate.
- Neagu E et al. (2018). Antioxidant activity, acetylcholinesterase and tyrosinase inhibitory potential of Pulmonaria officinalis and Centarium umbellatum extracts. PubMed 29686522.
- Haberer W et al. (2002). Pyrrolizidine alkaloids in Pulmonaria obscura. Planta Medica, 68(5), 480–482. PubMed 12058336.
- Pyrrolizidine Alkaloids in Pulmonaria obscura. ResearchGate full text.
- Pulmonaria officinalis. Wikipedia.
- Lobaria pulmonaria (Tree Lungwort). Wikipedia.
- Boraginaceae — overview including pyrrolizidine alkaloid content. ScienceDirect Topics.
- Pyrrolizidine Alkaloid-Induced Hepatotoxicity Associated with the Formation of Reactive Metabolite-Derived Pyrrole–Protein Adducts. PMC8540779.
- Lungwort: Health Benefits, Side Effects, Uses, Dose & Precautions. RxList (citing Natural Medicines Comprehensive Database).
- Plants for a Future (PFAF) — Pulmonaria officinalis database entry.
- Lungwort Benefits: Traditional Uses, Research, and Safety. Zuma Nutrition (2026).
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