Calendula is both a medicinal agent and culinary herb derived from the flowers of the marigold plant (Calendula officinalis). Calendula has been used for centuries in the treatment of various internal conditions such as stomach ulcers, liver diseases, worm infections, inflammation, dysmenorrhea, and poor circulation. Externally, calendula was traditionally applied to treat conditions of the skin (wounds), eye inflammations, varicose veins, and leg ulcers.
Current research is confirming its traditional use, finding that calendula may have health benefits, including: 
- digestive effects certain cosmetics and first aid formulations in Europe.
Calendula contains several bioactive principles in the flower’s essential oil that may provide for anti-inflammatory, immunity boosting, and wound-healing benefits. These constituents include faradiol (a triterpenoid) and helianol (a triterpene alcohol); both popular additives in cosmetic and first aid formulations in Europe. [2-6]
Research suggests that calendula may relieve inflammation and improve immunity by blocking certain inflammatory compounds and limiting the infiltration of white blood cells (an immune system response to inflammation) into tissues. [2-5] Modern science has also supported the hypothesis of calendula’s wound healing properties. Calendula has been found to stimulate the growth of new tissues and blood vessels when applied externally to wounds. 
Calendula is primarily used for its anti-inflammatory actions. This supplement may benefit inflammatory conditions of the eye and ear, and also those associated with soft tissue trauma. Study conducted on persons with wounds of various sorts, found a marked stimulation of skin regeneration and epithelialization of wounds when treated with calendula. 
One experimental study suggests that calendula may have anti-inflammatory effects that are similar to that of indomethacin, a non-steroidal anti-inflammatory drug.  Some studies have also found calendula to be effective in treating inflammatory diseases of the eyelids and conjunctiva. [7-9]
A study conducted on 103 children with acute otitis media reported a decrease in ear pain when treated with an herbal extract containing calendula. This extract was proven to be as equally effective as anesthetic ear drops. 
Calendula may also be used for its purported immune-stimulating effects. One experimental study found that calendula extract stimulates production of polysaccharide (heteroglycan) immune-stimulating compounds.  An in vitro study found that calendula may inhibit the human immunodeficiency virus type 1 (HIV-1).  However, more studies need to be conducted to determine calendula’s anti-HIV efficacy in human subjects.
Calendula may be helpful as an aid for digestive disorders such as gastric ulcers. An animal study has demonstrated that gastric ulcers were improved when treated with calendula.  As with HIV testing, more studies need to be done to determine calendula’s digestive benefits in humans.
Dosage: Ranges from 20 - 60 drops (1:1w/v fluid extract), taken 3-4 times daily. Apply topically as directed by product manufacturer.
Most Common Delivery Forms: Extract, topical cream. 
Calendula should not be taken by those individuals allergic to plants of the daisy family. Pregnant, lactating women, and children should not take supplemental calendula, unless recommended by a health care provider.
Side effects may include a slight chance (approximately 1 in 500) of a sensitivity reaction with the topical application of calendula. It is recommended that one always inform his/her health care provider about the dietary supplements being consumed, due to the potential development of side effects and/or allergy.
1. Balch JF, and Balch PA. Prescription for Nutritional Healing, 3rd ed. New York: Penguin Putnam Avery, 2000: 66.
2. Akihisa T et al. Triterpene alcohols from the flowers of compositae and their anti-inflammatory effects. Phytochemistry (US) Dec 1996, 43(6):1225-60
3. Shipochliev T et al. [Anti-inflammatory action of a group of plant extracts.] Vet Med Nauki (Bulgaria) 1981 18(6):87094
4. Della Loggia R, et al. The role of triterpenoids in the topical anti-inflammatory activity of Calendula officinalis flowers.Planta Med. Dec1994;60(6):516-20.
5. Wagner H, et al. Immunostimulating action of polysaccharides (heteroglycans) from higher plants. Arzneimittelforschung. 1985;35(7):1069-75.
6. Klouchek-Popova E, et al. Influence of the physiological regeneration and epithelialization using fractions isolated from Calendula officinalis. Acta Physiol Pharmacol Bulg. 1982;8(4):63-7.
7 Mozherenkov VP, et al. Treatment of chronic conjunctivitis with Calendula. Med Sestra. Apr1976;35(4):33-4.
8. Marinchev VN, et al. Use of calendula for therapy of chronic inflammatory diseases of eyelids and conjunctiva. Oftalmol Zh. 1971;26(3):196-8.
9. Calendula, Dietary Supplement Information Bureau:
10. 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. Jul2001;155(7):796-9.
11. Kalvatchev Z, et al. Anti-HIV activity of extracts from Calendula officinalis flowers. Biomed Pharmacother. 1997;51(4):176-80.
12. Yoshikawa M, Murakami T, Kishi A, Kageura T, Matsuda H. Medicinal flowers. III. Marigold. (1): hypoglycemic, gastric emptying inhibitory, and gastroprotective principles and new oleanane-type triterpene oligoglycosides, calendasaponins A, B, C, and D, from Egyptian Calendula officinalis. Chem Pharm Bull. Tokyo. Jul2001;49(7):863-70.
13. Calendula, PDR Health: http://www.pdrhealth.com/drug_info/nmdrugprofiles/herbaldrugs/101840.shtml