Calendula, also known as marigold, has been widely used on the skin to treat minor wounds, skin infections, burns, bee stings, sunburn, warts, and cancer. Most scientific evidence regarding its effectiveness as a wound-healing agent is based on animal and laboratory study, while human research is virtually lacking.
One study in breast cancer patients receiving radiation therapy suggests that calendula ointment may be helpful in preventing skin dermatitis (irritation, redness, and pain).
Synonyms
Allo-ocimene, Asteraceae (family), bride of the sun, bull flower, butterwort, Calendula arvensis L., Calendula micrantha, Calendula officinalis, calendula flower, calendula herb, calendulae flos, calendulae herba, Caltha officinalis, calypso orange florensis, cis-tagetone, claveton (Spanish), Compositae (family), cowbloom, death-flower, dihydro tagetone, drunkard gold, Fiesta Gitana Gelb, fior d'ogni (Italian), flaminquillo (Spanish), fleurs de tous les mois (French), gauche-fer (French), gold bloom, goldblume (German), golden flower of Mary, goulans, gouls, holligold, holygold, husband's dial, kingscup, Laser Activated Calendula Extract (LACE), limonene, lutein, maravilla, marybud, marigold, marigold dye, marigold flowers, may orange florensis, marygold, mejorana (Spanish), methyl chavicol, patuletin, patulitrin, piperitenone, piperitone, poet's marigold, pot marigold, publican and sinner, Ringelblume (German), ruddles, Scotch marigold, shining herb, solsequia, souci (French), souci des champs (French), souci des jardins (French), summer's bride, sun's bride, T. florida Sweet, Tagetes lucida (Asteraceae), Tagetes maxima, Tagetes patula (Asteraceae), T. schiedeana, water dragon, yolk of egg.
Note: Calendula or marigold should not be confused with the common garden or French marigold (Tagetes), African marigold (T. erecta), or Inca marigold (T. minuta).
Uses Based on Tradition or Theory
The uses listed below are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Abscesses, acne, anemia, anti-inflammatory, antioxidant, antiviral, anxiety, appetite stimulant, atherosclerosis (clogged arteries), athlete's foot, bacterial infections, benign prostatic hypertrophy, bladder irritation, blood purification, blood vessel clots, bowel irritation, bruises, cancer, cholera, circulation problems, conjunctivitis, constipation, contact dermatitis, cosmetic, cough, cramps, detoxification (purging agent), diabetes, diaper rash, diaphoresis (sweating), diarrhea, dizziness, diuretic, dystrophic nervous disturbances, eczema, edema, epididymitis, eye inflammation, fatigue, fever, frostbite, fungal infections, gastrointestinal inflammation, gastrointestinal tract disorders, gingivitis, gout, gum disease prevention, headache, heart disease, hemorrhoids, herpes keratitis, herpes simplex virus infections, high cholesterol, HIV, immune system stimulant, immunomodulation, indigestion, influenza, insomnia, jaundice, kidney or bladder stones, liver cancer, liver dysfunction, liver-gallbladder function stimulator, menstrual period abnormalities, metabolic disorders, migraine, mouth and throat infections, mosquito repellant, muscle spasms, muscle wasting, nausea, nervous system disorders, nosebleed, oral hygiene, pain, parasite infection, prostatitis, ringing in the ears, skin cancer, skin irritation, sore throat, spleen disorders, syphilis, toothache, tuberculosis, ulcerative colitis, peptic ulcer disease, urinary retention, uterine problems, varicose veins, varicose ulcers, venous disorders (phlebitis, thrombophlebitis), vitamin deficiencies (lutein or beta-carotene), warts, yeast infections.
What the Science Says
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Radiation skin protection
A study in women receiving radiation therapy to the breast for breast cancer reports that calendula ointment applied to the skin at least twice daily during treatment reduces severe dermatitis (skin irritation, redness, pain). However, this study cannot be considered conclusive due to limitations of its design. Based on this evidence, this approach may be considered in patients who experience radiation dermatitis that cannot be controlled with other therapies.
Ear infection
Calendula has been studied for reducing pain caused by ear infections. Some human studies suggest that calendula may possess mild anesthetic (pain-relieving) properties equal to those of similar non-herbal eardrop preparations. Further studies are needed before a recommendation can be made in this area.
Skin inflammation
Limited animal research suggests that calendula extracts may reduce inflammation when applied to the skin. Human studies are lacking in this area.
Wound and burn healing
Calendula is commonly used on the skin to treat minor skin wounds. Reliable human research is necessary before a firm conclusion can be drawn.
Side Effects and Warnings
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Aside from allergic reactions, few severe reactions have been found in published reports. In one small animal study, calendula was associated with a fatal reduction in blood glucose, accompanied by decreased serum lipids and protein. Skin (atopic dermatitis) and eye irritation have been reported.
Allergies
People with allergies to plants in the Aster/Compositae family, such as ragweed, chrysanthemums, marigolds, and daisies, are more likely to have an allergic reaction to calendula. There is one case of a severe allergic reaction (anaphylactic shock) after gargling with a calendula preparation.
Pregnancy & Breastfeeding
It is not clear if calendula is safe for use during pregnancy or breastfeeding. In animal studies, calendula has had effects on the uterus, and calendula has traditionally been thought to have harmful effects on sperm and to cause abortions. However, it is not clear if these effects occur with use of calendula on the skin.
Interactions
Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.
Interactions with Drugs
In early animal studies, high doses of calendula were reported to cause drowsiness. It is not clear if the use of calendula on the skin of humans has this effect. In theory, the use of calendula in combination with sedative drugs may lead to increased drowsiness. Examples include benzodiazepines such as lorazepam or diazepam, barbiturates such as phenobarbital, narcotics such as codeine, some antidepressants, and alcohol. Caution is advised while driving or operating machinery.
In early animal studies, high doses of calendula preparations were reported to lower blood pressure. It is not clear if the use of calendula on the skin of humans has this effect. In theory, the use of calendula in combination with drugs that lower blood pressure may lead to increased effects.
Calendula may also increase the effects of antispasmodics, which are drugs that help stop muscle spasms.
Use cautiously if taking drugs that can damage the liver or kidneys because calendula may increase the risk of organ damage.
Other possible interactions include increases in the activity of hypoglycemic (diabetic) medications or insulin, antifungal medications, or agents that decrease lipids and triglycerides (cholesterol-lowering drugs.)
Interactions with Herbs and Dietary Supplements
In early animal studies, high doses of calendula were reported to cause drowsiness. It is not clear if the use of calendula on the skin of humans has this effect. Use of calendula in combination with herbs or supplements that have possible sedative effects may lead to increased drowsiness. Caution is advised while driving or operating machinery.
In early animal studies, high doses of calendula preparations were reported to lower blood pressure. It is not clear if the use of calendula on the skin of humans has this effect. In theory, the use of calendula in combination with herbs that may lower blood pressure may lead to increased effects.
Other possible interactions include increases in the activity of hypoglycemic (diabetic) medications or insulin, antifungals, or agents that decrease lipids and triglycerides (cholesterol-lowering agents).
Calendula may also increase the effects of herbs or supplements that help stop muscle spasms (antispasmodics).
Use cautiously if taking herbs or supplements that can damage the liver or kidneys because calendula may increase the risk of organ damage.
Since the stem and leaves of calendula contain lutein and beta-carotene, a possible supplement interaction exists with products that contain these ingredients.
The FDA does not have the authority to test or approve the safety of herbal products before they are available for your consumption. Since the FDA does not regulate herbal products, there is no guarantee of the strength, purity or safety of herbal products; so effects may vary.
Just because an herbal product is labeled "natural" does not mean it is safe. Herbal supplements and remedies may have harmful effects and can interact with prescription and over-the-counter medications to cause severe side effects and complications.
Read product labels. Speak with your doctor before using any herbal remedy or supplement. Tell your doctor about any herbal remedies you already use and about any complementary and alternative practices you use. Give him/her a full picture of what you do to manage your health. This will help ensure coordinated and safe care. Call your doctor if you experience side effects.
The content of this posting comes from the National Institutes of Health.
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Deborah White, MD, MBA