How It Works
Bottom Line: Topical application of calendula may reduce painful swelling and irritation associated with radiation therapy. It has not been shown to treat cancer in humans.
Naturally occurring chemicals derived from the marigold plant have been shown to reduce inflammation in laboratory studies. These chemicals, which are called triterpenoids, also have been shown to inhibit HIV virus and certain tumor cells. When applied to the skin, extracts of Calendula may help to heal wounds and inflammation after radiation therapy.
Purported Uses
To heal burns and scalds
Laboratory and animal studies show that Calendula, applied to the skin, may have anti-inflammatory properties, and Calendula reduced burn tissue injury in animals. However, studies have not been undertaken to determine if this corresponds to faster healing of burns and scalds. Also, clinical studies in humans have not been performed.
To treat painful menstruation
No scientific evidence supports this use.
To prevent skin inflammation
Calendula ointment applied to the skin reduced painful swelling and irritation associated with radiation therapy in breast cancer patients.
To treat spasms
No scientific evidence supports this use.
To treat varicose veins
No scientific evidence supports this use.
Research Evidence
Radiation Therapy Side Effects: Two hundred fifty-four breast cancer patients undergoing radiation therapy participated in a trial of Calendula to see if it would reduce skin inflammation due to radiation therapy. The patients were randomly assigned to receive a topical ointment containing either Calendula or trolamine. Trolamine is an accepted treatment for skin inflammation. Subjects who used Calendula had fewer cases of severe skin inflammation. Because the texture, color, and smell of the two ointments were quite different, patients knew which treatment they were receiving. Researchers did not know which treatment they had received. This study suggests of Calendula ointment may be used as a preventative treatment for skin inflammation due to radiation therapy.
Warnings
This product is regulated by the FDA as a dietary supplement. Unlike approved drugs, supplements are not required to be manufactured under specific standardized conditions. This product may not contain the labeled amount or may be contaminated. In addition, it may not have been tested for safety or effectiveness.
Do Not Take If
You are allergic to plants in the Asteraceae/Compositae family (You may have a reaction.)
You are pregnant or lactating (traditionally, calendula is reported to affect the menstrual cycle.)
Scientific Name
Calendula officinalis
Common Name
Gold-bloom, Marigold, Marybud, Pot Marigold
Clinical Summary
Extracted from the flower of the marigold plant of the Compositae family, calendula is used topically for wound healing
(1). Major constituents of the leaves and stems of the plant include lutein and beta-carotene
(2). Extracts from calendula have been shown to have anti-inflammatory properties
(3), which may improve wound healing
(4), and antibacterial, anti-parasitic
(5), and anti-HIV
(6) effects in vitro. A formulation that includes calendula as well as a variety of other herbs was shown to be effective in reducing earache in children with acute otitis media
(7)(8).
Some in vitro and in vivo studies suggest that calendula has cytotoxic and anti-tumor activities
(9)(10). Preliminary data support use of topical calendula for prophylaxis of acute dermatitis during radiation therapy in cancer patients
(11) (13).
Calendula has been known to cause allergic reactions
(1) (12).
Purported uses
Conjunctivitis
Eczema
GI disorders
Inflammation
Menstrual cramps
Menstrual disorder
Radiation therapy side effects
Spasms
Varicose veins
Constituents
Flavonoids: Polysaccharides, Triterpenoids (oleanolic acid), Volatile Oils, Other
(1).
Mechanism of Action
Triterpenoids from Calendula have been shown to have anti-inflammatory
(3) (6) and anti-HIV activities
(2). The most active triterpenoid is a monoester of faradiol
(1). The organic extract of calendula has been shown to suppress cell fusion which may inhibit early events in the HIV replication cycle
(6). Extracts from calendula were shown to be cytotoxic and exhibit antitumor activity in mouse Ehrlich carcinoma model, although the effects were not always consistent
(9).
Contraindications
Calendula should be avoided during pregnancy and lactation
(1).
Adverse Reactions
Calendula may cause allergic reactions
(1) (12).
Literature Summary and Critique
References
1. Barnes J, Anderson LA, Phillipson JD. Herbal Medicines. London: Pharmaceutical Press; 2002.
2. Bako E, Deli J, Toth G. HPLC study on the carotenoid composition of Calendula products. J Biochem Biophys Methods. Oct-Nov 2002;53(1-3):241-250.
3. Akihisa T, Yasukawa K, Oinuma H, et al. Triterpene alcohols from the flowers of compositae and their anti-inflammatory effects. Phytochemistry. Dec 1996;43(6):1255-1260.
4. Chandran PK, Kuttan R. Effect of Calendula officinalis Flower Extract on Acute Phase Proteins, Antioxidant Defense Mechanism and Granuloma Formation During Thermal Burns. J Clin Biochem Nutr. Sep 2008;43(2):58-64.
5. Szakiel A, Ruszkowski D, Grudniak A, et al. Antibacterial and Antiparasitic Activity of Oleanolic Acid and its Glycosides isolated from Marigold (Calendula officinalis).Planta Med. Nov 2008;74(14):1709-1715.
6. Kalvatchev Z, Walder R, Garzaro D. Anti-HIV activity of extracts from Calendula officinalis flowers. Biomed Pharmacother. 1997;51(4):176-180.
7. Sarrell EM, Cohen HA, Kahan E. Naturopathic treatment for ear pain in children. Pediatrics. May 2003;111(5 Pt 1):e574-579.
8. Sarrell EM, Mandelberg A, Cohen HA.Efficacy of naturopathic extracts in the management of ear pain associated with acute otitis media. Arch Pediatr Adolesc Med. Jul 2001;155(7):796-799.
9. Boucaud-Maitre Y, Algernon O, Raynaud J. Cytotoxic and antitumoral activity of Calendula officinalis extracts. Pharmazie. Mar 1988;43(3):220-221.
10. Ukiya M, Akihisa T, Yasukawa K, et al. Anti-inflammatory, anti-tumor-promoting, and cytotoxic activities of constituents of marigold (Calendula officinalis) flowers. J Nat Prod. Dec 2006;69(12):1692-1696.
11. Pommier P, Gomez F, Sunyach MP, et al. Phase III randomized trial of Calendula officinalis compared with trolamine for the prevention of acute dermatitis during irradiation for breast cancer. J Clin Oncol. Apr 15 2004;22(8):1447-1453.
12. Reider N, Komericki P, Hausen BM, et al. The seamy side of natural medicines: contact sensitization to arnica (Arnica montana L.) and marigold (Calendula officinalis L.). Contact Dermatitis. 2001 Nov;45(5):269-72.
13. Kassab S, Cummings M, Berkovitz S, et al. Homeopathic medicines for adverse effects of cancer treatments. Cochrane Database Syst Rev. 2009 Apr 15;(2):CD004845. Review.
