Phytotherapy · Skin Healing & Anti-inflammatory · Asteraceae

Calendula

Calendula officinalis (Asteraceae) — the orange-flowered garden marigold whose flower heads are among the best-studied topical herbs for wounds and skin inflammation. Its faradiol triterpenes drive documented anti-inflammatory and anti-oedematous activity, with clinical research in leg ulcers, burns, diaper dermatitis, and radiotherapy dermatitis.

51 Primary Refs
12 Properties
Flowers Parts Used
✦ Researched
Last Updated October 24, 2026
Primary Source Wikiphyto · NCBI PubMed · Radiotherapy Trial
Family Asteraceae
Annual or Biennial Herb · Ornamental

Botanical Overview

Calendula is an ornamental, aromatic herb native to southern Europe, with a branching, hairy stem and broad, lance-shaped alternate leaves. Its terminal flower heads (capitula), 4 to 7 cm across, carry many orange-yellow ray and disc florets and bloom throughout the summer.

HabitAnnual or biennial
Height30–50 cm
Flower Head4–7 cm across
FloweringThroughout summer
Taxonomic Classification

Taxonomy & Identification

Latin Name
Calendula officinalis L.
Family
Asteraceae
Common Names
Calendula, Marigold, Souci des jardins
Parts Used
Flower heads (capitula)
Native Range
Southern Europe
Regulatory Status
French Pharmacopoeia, list A (capitulum, flower)
Ethnobotany & Traditional Use

History & Tradition

Calendula is a long-cultivated garden plant of southern Europe, noted for its flowers, which follow the sun's path through the day. It is listed in the French Pharmacopoeia (list A, capitulum and flower) and recognized by Germany's Commission E.

Modern research has focused on its triterpene-driven anti-inflammatory effect, and on clinical use in wounds, ulcers and radiotherapy dermatitis. The EMA publishes a monograph on calendula flowers. 11518

⚠ Asteraceae Allergy

Calendula belongs to the Asteraceae (daisy) family and is contraindicated in people with hypersensitivity to marigold or an allergy to Asteraceae. See Safety & Interactions.

Timeline

Garden & Folk Use

Traditional

Cultivated as an ornamental and aromatic herb in southern Europe, and used for wounds and skin inflammation.

Radiotherapy Dermatitis Trial

2004

A phase III trial compares calendula with trolamine for acute dermatitis in breast cancer radiotherapy. 38

Leg Ulcer Studies

2005–2016

Clinical studies in venous, diabetic and pressure ulcers. 1920

EU Herbal Monograph

2018

The EMA publishes its monograph on Calendula officinalis flowers.

The Key Compounds

Faradiol & Triterpenes — Deep Dive

The triterpenic alcohols and their esters carry most of calendula's topical anti-inflammatory activity.

🧬

Faradiol Monoesters

Make up about 2.4% of the dried flower (2.9% of dried ray florets); the lauryl, myristic and palmitic faradiol esters are the most abundant and appear most active. 52

🔥

Anti-Inflammatory & Anti-Oedematous Action

Triterpenoids, notably faradiol esters, are responsible for the topical anti-inflammatory and anti-oedematous effect. 1011121314

🧪

Triterpenoid Saponins (2–10%)

Six saponins (A–F) with oleanolic acid; amphiphilic, abundant and haemolytic, which is why oral use is discouraged. 48

🌼

Variety Matters

Varieties with more ray florets may be more active, because faradiol monoesters concentrate in the ray florets. 40

Pharmaceutical Preparations

Parts Used & Available Forms

The flower heads (capitula) are used, prepared in three documented forms.

Mother Tincture

Teinture-mère of the flowering tops.

Liquid Extract

Hydroalcoholic Extract

40–90% v/v ethanol, with a flower-to-extract ratio of 1:1 to 1:5. 1

Extract

Macerated Oil

Flower-to-macerate ratio of 1:5 to 1:25; final preparations contain 2–20% flower equivalent. 1

Topical Oil

Clinical Dosimetry

Dosages

Calendula is used mainly topically; the EMA documents the frequency of application, and one trial tested an oral extract.

Form Dose Frequency Context Notes
Topical Preparations 2–20% flower equivalent (macerated oil or extract) 2–4 applications per day Wounds and skin inflammation EMA monograph. 1
Oral Extract 2 g Per day for 14 days Second-degree burns Sped burn healing in one study; oral use is otherwise discouraged. 41
Phytochemistry

Composition

Triterpenes and saponins dominate calendula's activity, alongside flavonoids, carotenoids and a small essential-oil fraction; no gemmotherapy (bud) fraction is documented.

Triterpenes & Saponins

Triterpenoid Saponins2–10%: six saponins (A–F), oleanolic acid, faradiol
Present
Triterpenic AlcoholsUnder 5% in total, mostly as esters: monols (~0.8%: ψ-taraxasterol, α- and β-amyrin, lupeol, taraxasterol) and diols (~4%: faradiols, arnidiol) 234
Present
Faradiol Monoesters2.9% of dried ray florets (about 2.4% of dried flower); lauryl, myristic and palmitic esters most abundant 5
Present
Other Triterpenic AlcoholsTaraxasterol, calenduladiol, lupeol, β-amyrin 6
Present

Pigments, Flavonoids & Others

Carotenoids0.2–3.5% of dried flower; flavoxanthin, lutein, β-carotene, lycopene and others 789
Present
FlavonoidsQuercetol and isorhamnetol
Present
Essential Oil0.2–0.3%, mainly sesquiterpenes: α-cadinol (~25%), T-cadinol, α- and β-ionones, dihydroactinidiolide
Present
Mucilages & PhytosterolsGeneral constituents
Present

Plant Properties — Pharmacodynamics

Twelve pharmacodynamic properties are documented for calendula, led by its topical anti-inflammatory and wound-healing activity.

12 Properties Anti-Inflammatory Wound Healing Clinical + Preclinical
🔥

Topical Anti-Inflammatory

Mainly from triterpenic alcohols such as faradiol. 10111314

💧

Anti-Oedematous & Astringent

Reduces oedema; also astringent, haemostatic and healing. 12161715

🩹

Wound Healing

In acute wounds it resolves inflammation and increases granulation tissue; extracts also speed epithelialisation. 1826

🦵

Chronic Ulcers

Reduces the area of venous leg ulcers, and has been studied in diabetic-foot and pressure ulcers. 19202122

👶

Dermatitis & Burns

Reduces rash in diaper dermatitis; results in burns were mixed in a systematic review. 2324

☢️

Radiodermatitis Prevention

Prevents acute dermatitis after breast cancer radiotherapy; a Cochrane review supports topical use for prophylaxis. 3839

🛡️

Immunostimulant

Stimulates granulocyte formation and phagocytosis; a possible anti-HIV effect has been reported in vitro. 2537

✨

Skin Antioxidant

Raises collagen synthesis and reduces skin oxidative stress through polyphenols and flavonoids such as rutin and narcissin. 26

🫁

Antiasthmatic & Antihistamine

Antihistamine, anticholinergic, antispasmodic and mast-cell stabilising effects in animal asthma models. 27

🦠

Antibacterial & Antifungal

Antibacterial, and antifungal activity reported as comparable to fluconazole. 2930313233

🎯

Cytotoxic & Antimutagenic

Cytotoxic and antitumor in vitro, and antimutagenic through saponins. 343536

💊

Analgesic & Antispasmodic

Documented as an oral analgesic and antispasmodic (no references given).

Clinical Applications

Clinical Indications

Calendula's strongest evidence is topical, for wound and skin healing and the prevention of radiotherapy dermatitis.

🩹
Wounds & Skin Inflammation
Primary Indication
  • Wounds & Delayed Healing: a core indication, with systematic reviews supporting acute-wound healing. 1518
  • Leg Ulcers: reduces venous leg ulcer area in clinical studies. 1920
  • Skin Conditions: bruises, boils, acne, burns and dermatitis, including diaper dermatitis. 23
🔥
Burns & Radiotherapy
Documented Indication
  • Second-Degree Burns: an oral extract of 2 g/day for 14 days sped healing in one study. 41
  • Radiotherapy Burns & Skin Tumours: a documented use. 42
  • Radiation Dermatitis Prevention: effective in breast cancer radiotherapy. 3839
👄
Mouth, Throat & Stomach
Traditional Indication
  • Pharyngitis: as a mouthwash or gargle (no reference given).
  • Gastric Ulcers: a traditional use (no reference given). 28
🌸
Women's Health & Other Uses
Documented & Uncertain
  • Bacterial Vaginosis: a methanolic extract was comparable to metronidazole in a double-blind trial. 43
  • Detoxification & Hepatoprotection: documented in reviews. 4445
  • Psoriasis (Oral) (?): flagged with a question mark in the source literature, so this use is considered uncertain.
Pharmacodynamics

Mode of Action

Calendula acts through triterpene anti-inflammatory activity, polyphenol antioxidant effects, and saponin surfactant properties.

🔥

Triterpene-Mediated Anti-Inflammatory Action

Triterpenic alcohols, particularly faradiol esters, drive the topical anti-inflammatory and anti-oedematous effect. 101216

✨

Polyphenols, Collagen & Oxidative Stress

Polyphenols and flavonoids (rutin, narcissin) speed epithelialisation, raise collagen synthesis, and reduce skin oxidative stress. 2617

🛡️

Mast-Cell Stabilisation

Antihistamine, anticholinergic and mast-cell stabilising effects were shown in animal asthma models. 27

🧪

Saponin Surfactant Properties (Presumed)

Saponins are amphiphilic, giving surfactant and foaming properties; they are generally cholesterol-lowering, induce mucus secretion, and thin mucus via a vagal reflex, and some are immunostimulant. They may also protect the plant against microbes and fungi.

Clinical Safety

Safety & Interactions

Topical calendula is generally well tolerated; oral use is discouraged and Asteraceae allergy is a contraindication.

⚠️

Adverse Effects & Precautions

  • Oral Use Discouraged: toxicity is attributed to its abundant, haemolytic saponins. 48
  • Genotoxicity Suspected: mutagenicity is not established. 4950
  • Mouse Toxicology: no acute oral toxicity and no chronic toxicity up to 5 g/kg orally, though mild signs of kidney and liver overload (raised urea and transaminases) were noted. 51
🚫

Contraindications & Regulation

  • Allergy: contraindicated in hypersensitivity to marigold or allergy to Asteraceae. The National Toxicology Program found insufficient data to establish safety in cosmetic formulations. 46
  • Pregnancy & Breastfeeding: topical use is not contraindicated. In rats, a hydroalcoholic extract showed no toxic effects in early or mid-pregnancy but reduced fetal weight gain, and did not affect male fertility. 47
  • Drug Interactions: none are listed in the source literature.
  • Regulatory Status: French Pharmacopoeia, list A (capitulum, flower), and recognized by Germany's Commission E.
Clinical Disclaimer: This information is for educational purposes only and is not a substitute for professional medical advice. Consult a qualified healthcare provider before using calendula on open wounds, during radiotherapy, in pregnancy, or if you have an allergy to Asteraceae plants.
Common Questions

Frequently Asked Questions

What is calendula used for?
Calendula (Calendula officinalis) is used topically for wounds, skin and mucosal inflammation, delayed healing, bruises, boils, acne, burns, dermatitis and leg ulcers. It is also used as a mouthwash or gargle for pharyngitis, and has been studied for preventing radiotherapy dermatitis.
Does calendula help wounds heal?
Yes. Systematic reviews report that calendula extract helps resolve inflammation and increases granulation tissue in acute wounds, and clinical studies show it reduces the area of venous leg ulcers. Results in burns were mixed in a systematic review.
How often should calendula be applied?
The EMA monograph documents 2 to 4 applications per day of topical preparations, such as a macerated oil containing 2 to 20% flower equivalent. An oral extract of 2 g per day for 14 days sped healing of second-degree burns in one study.
Can calendula prevent radiation dermatitis?
A phase III randomized trial compared calendula with trolamine for preventing acute dermatitis during breast cancer radiotherapy and found calendula effective. A Cochrane review supports topical use for dermatitis prophylaxis during radiotherapy.
Is calendula good for diaper rash?
A randomized comparative trial found that topical calendula and aloe vera reduced rash in children with diaper dermatitis.
Is calendula safe to use?
Topical calendula is generally well tolerated, but it is contraindicated in people with hypersensitivity to marigold or an allergy to Asteraceae plants. Oral use is discouraged because its saponins are abundant and haemolytic, and genotoxicity is suspected though mutagenicity has not been established.
Can I use calendula during pregnancy or breastfeeding?
Topical use in pregnancy or breastfeeding is not contraindicated. In rats, a hydroalcoholic extract showed no toxic effects in early or mid-pregnancy but reduced fetal weight gain, and it did not affect male fertility.
What are the active compounds in calendula?
The main anti-inflammatory compounds are triterpenic alcohols, especially faradiol and its esters, alongside triterpenoid saponins (2 to 10%), flavonoids such as quercetol and isorhamnetol, and carotenoids (0.2 to 3.5% of the dried flower).
Can calendula treat bacterial vaginosis?
A double-blind randomized trial found that a methanolic calendula extract was comparable to metronidazole for bacterial vaginosis, but this is a single study and should be treated as preliminary.
Sources

Bibliography

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Full Text →
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↑24. Givol O, Kornhaber R, Visentin D, et al. A systematic review of Calendula officinalis extract for wound healing. Wound Repair Regen. 2019;27(5):548–561. (Same study as reference 18, cited a second time in the original source.)
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Full Text →
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Additional Sources

Basch E, Bent S, Foppa I, et al.; Natural Standard Research Collaboration. Marigold (Calendula officinalis L.): an evidence-based systematic review by the Natural Standard Research Collaboration. J Herb Pharmacother. 2006;6(3–4):135–159.
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Ghédira K, Goetz P. Calendula officinalis L. (Asteraceae): Souci. Phytothérapie. 2016;14:62–67.