Plant Comparison
Chili Pepper vs Common Comfrey
A side-by-side comparison of two medicinal plants — every documented constituent, action, use, safety note and cited source, assembled automatically from the Omnia Sana database.
At a glance
Chili Pepper and Common Comfrey: they share 7 indicated uses (arthritis / joint pain, back pain, headache, …); 2 pharmacological actions in common.
Evidence face-off — shared uses
| Condition | Chili Pepper | Common Comfrey | Verdict |
|---|---|---|---|
| Arthritis / joint pain | 6/10 | 5/10 | Comparable evidence |
| Back pain | 6/10 | 5/10 | Comparable evidence |
| Headache | 1/10 | 5/10 | Stronger for Common Comfrey |
| Inflammation (general) | 1/10 | 5/10 | Stronger for Common Comfrey |
| Pain (general) | 6/10 | 8/10 | Stronger for Common Comfrey |
| Skin irritation | 1/10 | 5/10 | Stronger for Common Comfrey |
| Wounds | 1/10 | 5/10 | Stronger for Common Comfrey |
Evidence scores (1–10) are computed from the tier of each cited source. “Comparable” means the two scores are within one point. Follow a score to its detailed sources.
Key Constituents
The pungent alkaloid-like compounds responsible for the fruit's heat and its counterirritant/analgesic action via TRPV1 receptor desensitisation.
Give ripe red fruit its colour and contribute antioxidant and anti-inflammatory activity.
Antioxidant and anti-inflammatory flavonoids identified in leaf and fruit extracts.
The key cell-proliferative constituent underlying comfrey's wound-healing reputation.
Contribute to the soothing, demulcent texture of the leaf and root.
Contribute to antioxidant and anti-inflammatory activity.
Hepatotoxic constituents naturally present in the whole plant; the reason internal use is not recommended and processed/detoxified extracts are used for research.
Pharmacological Actions
Traditional & Indicated Uses
inferred from anti-inflammatory action
inferred from analgesic action
inferred from digestive action
inferred from antimicrobial action
inferred from anti-inflammatory action
inferred from anti-inflammatory action
inferred from anti-inflammatory action
inferred from anti-inflammatory action
inferred from anti-inflammatory action
inferred from anti-oedematous action
Safety, Cautions & Contraindications
Capsaicin causes intense burning sensation; avoid contact with eyes and mucous membranes. High oral doses can cause gastrointestinal irritation, nausea, and diarrhoea. Topical preparations may cause skin irritation and should be used diluted. Not recommended for individuals with active peptic ulcers. Caution with anticoagulants — capsaicin may enhance bleeding risk. During pregnancy, culinary amounts are considered safe, but high-dose supplements should be avoided. Repeated topical application leads to desensitisation (TRPV1 depletion), which is the basis for its analgesic use. Children under 2 should not be given capsaicin-containing topical products (Basu and Bhattacharyya, 2023).
Duke (2002) rates cayenne/chili pepper (Capsicum annuum) highly for its clinically documented analgesic, counterirritant, and rubefacient activities. Commission E approves topical capsaicin preparations for muscle pain, arthritis, and neuralgia (score 2). The active compound capsaicin depletes substance P in sensory neurons upon repeated application, reducing pain signals. Capsaicin cream (0.025–0.075%) is a validated treatment for post-herpetic neuralgia, diabetic neuropathy, and osteoarthritis pain. Internal use can irritate mucous membranes; external use requires avoiding contact with eyes and mucous membranes (Duke, 2002).
Big headline: Comfrey naturally contains pyrrolizidine alkaloids (PAs), which can seriously harm the liver if taken internally (Staiger, 2012; EMA, 2015). • Do not ingest comfrey (no teas, no internal tinctures, no capsules), because PA exposure from internal use is the main safety problem (Staiger, 2012; Bach et al., 1990). • Topical use only, short-term: EU herbal guidance describes comfrey root preparations for minor bruises and sprains in adults, and recommends limited duration (commonly up to about 10 days) (EMA, 2015; EMA/HMPC, 2024). • Do not apply to broken skin (open wounds, damaged/irritated skin) and avoid eyes/mucous membranes (EMA/HMPC, 2024). • Pregnancy & breastfeeding: best avoided (not enough safety margin for medicinal use) (EMA/HMPC, 2024). • Children/adolescents: not recommended for medicinal topical use in EU monograph context (EMA/HMPC, 2024). • If you have liver disease or take medicines that stress the liver, skip comfrey completely (risk management logic based on PA concern) (Staiger, 2012; EMA, 2015). • Skin reactions: mild rash/irritation can occur; stop if it irritates (Smith and Jacobson, 2011).
Duke (2002) classifies common comfrey (Symphytum officinale) with anti-inflammatory and wound-healing properties, supported by allantoin content (promotes cell proliferation). However, comfrey also contains hepatotoxic pyrrolizidine alkaloids. Internal use is no longer recommended, and Commission E approved only external use. Duke emphasizes that pyrrolizidine alkaloids are cumulative hepatotoxins associated with veno-occlusive disease, and prolonged or internal use is contraindicated (Duke, 2002).
External Ids
Botanical Description
Bushy annual or short-lived perennial herb (grown as an annual in temperate climates) with glossy, oval to lance-shaped leaves. Small, star-shaped, white to greenish flowers give way to the characteristic fleshy, hollow fruit (a berry), which ripens from green through yellow to red and varies enormously in size, shape and pungency between cultivars.[1]
Robust, hairy perennial herb (Boraginaceae), 60-120 cm tall, with a thick, black-skinned, mucilaginous taproot. Leaves are large, broad, lance-shaped and bristly-hairy, running down the stem as raised wings (decurrent) - the leaf base's smooth, untoothed margin is a key feature distinguishing it from toxic foxglove. Drooping clusters of tubular, bell-shaped flowers are cream, pink or purple depending on variety.[11]
Habitat
Native to Central and South America; cultivated worldwide in warm and temperate climates as a food and medicinal crop, thriving in full sun on well-drained soil.[1]
Native to Europe and western Asia, growing in damp ground - riverbanks, ditches, damp meadows and waste ground - and widely cultivated.[11]
Harvesting
Fruit is picked at the desired stage of ripeness (green for milder use, fully red for maximum capsaicin and carotenoid content) through summer and autumn; seeds are separated and dried from fully ripe fruit.
Leaves are cut during the growing season (before flowering is often preferred for lower pyrrolizidine-alkaloid content); root is dug in autumn or spring from mature plants.[11]
Traditional Uses
Chili pepper fruit has a long history across the Americas and, after global spread, in many other traditional medicine systems as a warming digestive stimulant and topical counterirritant/analgesic for muscle and joint pain, building on capsaicin's now well-documented ability to desensitise pain-sensing nerve fibres with repeated application.[1]
Comfrey has one of the strongest traditional reputations of any European herb for wound healing and bone/tissue repair - the folk names 'knitbone' and 'boneset' reflect this - owing to its high allantoin content, which stimulates cell proliferation. Because the plant also contains hepatotoxic pyrrolizidine alkaloids, modern regulatory use is restricted to topical preparations only, for minor bruises and sprains, and internal use (teas, tinctures) is no longer recommended.[11]
Preparations
Standardised capsaicin cream or patch applied to the affected area for muscle, joint or nerve pain; repeated application depletes substance P and reduces pain signalling.
The officially recognised European herbal-monograph preparation, for minor bruises and sprains, short-term use only.
Dosage
The EU herbal monograph on Capsici fructus gives semi-solid dosage forms corresponding to 40-53 mg capsaicinoids per 100 g, applied as a thin layer to the affected area 2-4 times daily, in adults and elderly. For medicated plasters, a maximum of 1 plaster per day applied for at least 4 and up to 12 hours, with at least 12 hours before a new plaster is applied to the same area. Not recommended under 18 years. Expect an initial burning sensation that lessens with repeated use. Note the monograph covers hot chilli fruit (C. annuum var. minimum and small-fruited C. frutescens), not sweet peppers. Educational reference only, not a prescription.
EU herbal-monograph guidance describes comfrey root preparations applied topically for minor bruises and sprains in adults, for a limited duration (commonly up to about 10 days); do not apply to broken skin or near eyes/mucous membranes. Comfrey must never be taken internally (no teas, tinctures or capsules) because of its pyrrolizidine alkaloid content. Educational reference only, not a prescription.
References
Lookalikes Review
Dangerous Lookalikes
Not documented
References & Sources
- Cho, S.Y., Kim, H.W., Lee, M.K., Kim, H.J., Kim, J.B., Choe, J.S., Lee, Y.M. and Jang, H.H (2020) 'Antioxidant and anti-inflammatory activities in relation to the flavonoids composition of pepper (Capsicum annuum L.)', Antioxidants, 9(10), pp. 986. doi:10.3390/antiox9100986 Preclinical
https://doi.org/10.3390/antiox9100986 - Khan, F.A., Mahmood, T., Ali, M., Saeed, A. and Maalik, A (2014) 'Pharmacological importance of an ethnobotanical plant: Capsicum annuum L', Natural Product Research, 28(16), pp. 1267-1274. doi:10.1080/14786419.2014.895723 Meta-analysis / review
https://doi.org/10.1080/14786419.2014.895723 - Srinivasan, K (2016) 'Biological activities of red pepper (Capsicum annuum) and its pungent principle capsaicin: a review', Critical Reviews in Food Science and Nutrition, 56(9), pp. 1488-1500. doi:10.1080/10408398.2013.772090 Meta-analysis / review
https://doi.org/10.1080/10408398.2013.772090 - Hernandez-Perez, T., Gomez-Garcia, M.D.R., Valverde, M.E. and Paredes-Lopez, O (2020) 'Capsicum annuum (hot pepper): an ancient Latin-American crop with outstanding bioactive compounds and nutraceutical potential. A review', Comprehensive Reviews in Food Science and Food Safety, 19(6), pp. 2972-2993. doi:10.1111/1541-4337.12634 Meta-analysis / review
https://doi.org/10.1111/1541-4337.12634 - Sanati, S., Razavi, B.M. and Hosseinzadeh, H (2018) 'A review of the effects of Capsicum annuum L. and its constituent, capsaicin, in metabolic syndrome', Iranian Journal of Basic Medical Sciences, 21(5), pp. 439-448. doi:10.22038/IJBMS.2018.25200.6238 Meta-analysis / review
https://doi.org/10.22038/IJBMS.2018.25200.6238 - Mandal, S.K., Rath, S.K., Logesh, R., Mishra, S.K., Devkota, H.P. and Das, N (2023) 'Capsicum annuum L. and its bioactive constituents: a critical review of a traditional culinary spice in terms of its modern pharmacological potentials with toxicological issues', Phytotherapy Research, 37(3), pp. 965-1002. doi:10.1002/ptr.7660 Meta-analysis / review
https://doi.org/10.1002/ptr.7660 - Grojja, Y., Hajlaoui, H., Luca, S.V., Abidi, J., Skalicka-Wozniak, K., Zouari, S. and Bouaziz, M (2023) 'Untargeted phytochemical profiling, antioxidant, and antimicrobial activities of a Tunisian Capsicum annuum cultivar', Molecules, 28(17), pp. 6346. doi:10.3390/molecules28176346 Preclinical
https://doi.org/10.3390/molecules28176346 - Hernandez-Ortega, M., Ortiz-Moreno, A., Hernandez-Navarro, M.D., Chamorro-Cevallos, G., Dorantes-Alvarez, L. and Necoechea-Mondragon, H (2012) 'Antioxidant, antinociceptive, and anti-inflammatory effects of carotenoids extracted from dried pepper (Capsicum annuum L.)', Journal of Biomedicine and Biotechnology, 2012, pp. 524019. doi:10.1155/2012/524019 Preclinical
https://doi.org/10.1155/2012/524019 - Maji, A.K. and Banerji, P (2016) 'Phytochemistry and gastrointestinal benefits of the medicinal spice, Capsicum annuum L. (Chilli): a review', Journal of Complementary & Integrative Medicine, 13(2), pp. 97-122. doi:10.1515/jcim-2015-0037 Meta-analysis / review
https://doi.org/10.1515/jcim-2015-0037 - Marrelli, M., Menichini, F. and Conforti, F (2016) 'Hypolipidemic and antioxidant properties of hot pepper flower (Capsicum annuum L.)', Plant Foods for Human Nutrition, 71(3), pp. 301-306. doi:10.1007/s11130-016-0560-7 Preclinical
https://doi.org/10.1007/s11130-016-0560-7 - Song, C., Yu, C., Zhu, X., Luo, X., Zhang, Y., Meng, L., Luo, Y., Chang, H., Qin, C. and Liu, Y (2020) 'A new capsaicin-containing phenolic glycoside from Capsicum annuum L', Natural Product Research, 36(2), pp. 546-552. doi:10.1080/14786419.2020.1789983 Preclinical
https://doi.org/10.1080/14786419.2020.1789983 - European Medicines Agency (HMPC) (2015) 'European Union herbal monograph on Capsicum annuum L. var. minimum (Miller) Heiser and small fruited varieties of Capsicum frutescens L., fructus'. Available at: https://www.ema.europa.eu/en/documents/herbal-monograph/final-european-union-herbal-monograph-capsicum-annuum-l-var-minimum-miller-heiser-and-small-fruited-varieties-capsicum-frutescens-l-fructus_en.pdf Traditional / reference
https://www.ema.europa.eu/en/documents/herbal-monograph/final-european-union-herbal-monograph-capsicum-annuum-l-var-minimum-miller-heiser-and-small-fruited-varieties-capsicum-frutescens-l-fructus_en.pdf - Anand, P. and Bley, K (2011) 'Topical capsaicin for pain management: therapeutic potential and mechanisms of action of the new high-concentration capsaicin 8% patch', 107(4), pp. 490--502. doi:10.1093/bja/aer260 Clinical study
https://doi.org/10.1093/bja/aer260 - Basu, S. and Bhattacharyya, S (2023) 'Capsicum and capsaicin: a comprehensive review of chemistry, pharmacology, and therapeutic applications', 22(5), pp. 1413--1442. doi:10.1007/s11101-023-09875-8 Traditional / reference
https://doi.org/10.1007/s11101-023-09875-8 - Derry, S., Rice, A.S., Cole, P., Tan, T. and Moore, R.A (2017) 'Topical capsaicin (high concentration) for chronic neuropathic pain in adults'. doi:10.1002/http://14651858.CD007393.pub4 Randomized trial
https://doi.org/10.1002/http://14651858.CD007393.pub4 - Royal Botanic Gardens, Kew (n.d.) 'Capsicum annuum L'. Available at: https://powo.science.kew.org/taxon/urn:lsid:http://ipni.org:names:841033-1 Traditional / reference
https://powo.science.kew.org/taxon/urn:lsid:http://ipni.org:names:841033-1 - Molina-Torres, J., García-Chávez, A. and Ramírez-Chávez, E (1999) 'Antimicrobial properties of alkamides present in flavouring plants traditionally used in Mesoamerica', 64(3), pp. 241--248. doi:10.1016/S0378-8741(98)00131-4 Traditional / reference
https://doi.org/10.1016/S0378-8741(98)00131-4 - Lv, J., Qi, L., Yu, C. et al (2015) 'Consumption of spicy foods and total and cause specific mortality: population based cohort study'. doi:10.1136/bmj.h3942 Clinical study
https://doi.org/10.1136/bmj.h3942 - Duke, J.A (2002) 'Handbook of Medicinal Herbs, Second Edition'. Traditional / reference
https://scholar.google.com/scholar?q=Handbook%20of%20Medicinal%20Herbs%2C%20Second%20Edition
- Syarifah, A.N., Suryadi, H., Hayun, H., Simamora, A. and others (2023) 'Detoxification of comfrey (Symphytum officinale L.) extract using natural deep eutectic solvent (NADES) and evaluation of its anti-inflammatory, antioxidant, and hepatoprotective properties', Frontiers in Pharmacology, 14, pp. 1012716. doi:10.3389/fphar.2023.1012716 Preclinical
https://doi.org/10.3389/fphar.2023.1012716 - Melnyk, N., Popowski, D., Strawa, J.W., Przygodzinska, K. and others (2023) 'Skin microbiota metabolism of natural products from comfrey root (Symphytum officinale L.)', Journal of Ethnopharmacology, 318(Pt B), pp. 116968. doi:10.1016/j.jep.2023.116968 Preclinical
https://doi.org/10.1016/j.jep.2023.116968 - Trifan, A., Skalicka-Wozniak, K., Granica, S., Czerwinska, M.E. and others (2020) 'Symphytum officinale L.: Liquid-liquid chromatography isolation of caffeic acid oligomers and evaluation of their influence on pro-inflammatory cytokine release in LPS-stimulated neutrophils', Journal of Ethnopharmacology, 262, pp. 113169. doi:10.1016/j.jep.2020.113169 Preclinical
https://doi.org/10.1016/j.jep.2020.113169 - Brown, A.W., Stegelmeier, B.L., Colegate, S.M., Gardner, D.R. and others (2016) 'The comparative toxicity of a reduced, crude comfrey (Symphytum officinale) alkaloid extract and the pure, comfrey-derived pyrrolizidine alkaloids, lycopsamine and intermedine in chicks (Gallus gallus domesticus)', Journal of Applied Toxicology, 36(5), pp. 716-725. doi:10.1002/jat.3205 Preclinical
https://doi.org/10.1002/jat.3205 - Trifan, A., Wolfram, E., Esslinger, N., Grubelnik, A. and others (2021) 'Globoidnan A, rabdosiin and globoidnan B as new phenolic markers in European-sourced comfrey (Symphytum officinale L.) root samples', Phytochemical Analysis, 32(4), pp. 482-494. doi:10.1002/pca.2996 Preclinical
https://doi.org/10.1002/pca.2996 - Nastic, N., Borras-Linares, I., Lozano-Sanchez, J., Svarc-Gajic, J. and others (2020) 'Comparative Assessment of Phytochemical Profiles of Comfrey (Symphytum officinale L.) Root Extracts Obtained by Different Extraction Techniques', Molecules, 25(4), pp. 837. doi:10.3390/molecules25040837 Preclinical
https://doi.org/10.3390/molecules25040837 - Frost, R., MacPherson, H. and O'Meara, S (2013) 'A critical scoping review of external uses of comfrey (Symphytum spp.)', Complementary Therapies in Medicine, 21(6), pp. 724-745. doi:10.1016/j.ctim.2013.09.009 Meta-analysis / review
https://doi.org/10.1016/j.ctim.2013.09.009 - Trifan, A., Opitz, S.E.W., Josuran, R., Grubelnik, A. and others (2018) 'Is comfrey root more than toxic pyrrolizidine alkaloids? Salvianolic acids among antioxidant polyphenols in comfrey (Symphytum officinale L.) roots', Food and Chemical Toxicology, 112, pp. 178-187. doi:10.1016/j.fct.2017.12.051 Preclinical
https://doi.org/10.1016/j.fct.2017.12.051 - Dey, D., Jingar, P., Agrawal, S., Shrivastava, V. and others (2019) 'Symphytum officinale augments osteogenesis in human bone marrow-derived mesenchymal stem cells in vitro as they differentiate into osteoblasts', Journal of Ethnopharmacology, 248, pp. 112329. doi:10.1016/j.jep.2019.112329 Preclinical
https://doi.org/10.1016/j.jep.2019.112329 - Kuchta, K. and Schmidt, M (2020) 'Safety of medicinal comfrey cream preparations (Symphytum officinale s.l.): The pyrrolizidine alkaloid lycopsamine is poorly absorbed through human skin', Regulatory Toxicology and Pharmacology, 118, pp. 104784. doi:10.1016/j.yrtph.2020.104784 Preclinical
https://doi.org/10.1016/j.yrtph.2020.104784 - European Medicines Agency (2011) 'European Union herbal monograph on Symphytum officinale L., radix'. Traditional / reference
https://scholar.google.com/scholar?q=European%20Union%20herbal%20monograph%20on%20Symphytum%20officinale%20L.%2C%20radix - Royal Botanic Gardens, Kew (n.d.). Available at: https://powo.science.kew.org Traditional / reference
https://powo.science.kew.org - Staiger, C (2012) 'Comfrey: a clinical overview', 26(10), pp. 1441--1448. doi:10.1002/ptr.4612 Randomized trial
https://doi.org/10.1002/ptr.4612 - Duke, J.A (2002) 'Handbook of Medicinal Herbs, Second Edition'. Traditional / reference
https://scholar.google.com/scholar?q=Handbook%20of%20Medicinal%20Herbs%2C%20Second%20Edition - Vithayathil, M.K. and Edwards, M (2016) 'Comfrey herbal remedy causing second-degree heart block: do not be outfoxed by digitalis', BMJ Case Reports, 2016, pp. bcr2016216995. doi:10.1136/bcr-2016-216995 Clinical study
https://doi.org/10.1136/bcr-2016-216995 - Lin, C.C. and Yang, C.C. and Phua, D.H. and Deng, J.F. and Lu, L.H (2010) 'An outbreak of foxglove leaf poisoning', Journal of the Chinese Medical Association, 73(2), pp. 97-100. doi:10.1016/S1726-4901(10)70009-5 Clinical study
https://doi.org/10.1016/S1726-4901(10)70009-5 - Woodland Trust (2024) 'Foxglove (Digitalis purpurea)'. Available at: https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/plants/wild-flowers/foxglove/ Traditional / reference
https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/plants/wild-flowers/foxglove/
Generated automatically from the Omnia Sana plant database and its cited sources. For educational purposes only — not medical advice. Always consult a qualified practitioner before using medicinal plants.