Evidence-based·Last reviewed June 1, 2026·How we grade evidence

Calendula

Q: What is Calendula used for?

Calendula is used traditionally for various supportive purposes. Human evidence for specific health claims is generally limited, so it is best treated as a complementary option rather than a treatment.

Q: Is Calendula safe?

Calendula is generally well tolerated at typical doses, but quality varies between products. People who are pregnant, breastfeeding, taking prescription medications, or managing a medical condition should check with a healthcare provider first.

Q: How long does it take to work?

Effects of botanical supplements often take several weeks of consistent use, if they appear at all. Reassess after 8-12 weeks of regular use.

BotanicalBest with a meal

A traditional skin-and-mucosa botanical with real evidence for topical use — radiation dermatitis prevention, minor wound healing, and chemotherapy-induced oral mucositis. Oral / tea use has thin evidence and isn't where the data sits. Generally well tolerated; ragweed-family allergy is the main exclusion.

Quick decision guide

May help most

Topical adjunct for radiation-induced skin reactions, minor wounds, and oral mucositis from chemo/radiotherapy. Traditional use for minor skin inflammation and chapped skin.

Common dosing range

Topical: 2–5% calendula ointment or cream applied 2–3 times daily to intact or partially intact skin. Oral mouthwash: calendula tincture 2% diluted in water, swish 2× daily.

When to expect effects

Days for symptom relief on minor inflammation; weeks for chronic wound healing.

Watch out for

Don't use on deep, infected, or actively bleeding wounds without clinician guidance. Avoid if you have a known Asteraceae allergy (ragweed, chamomile, arnica). Oral use during pregnancy is not recommended due to uterine-stimulant concerns from traditional sources.

Evidence snapshot

Radiation dermatitis (topical)Moderate

Minor wound healing (topical)Emerging

Chemo-induced oral mucositis (mouthwash)Emerging

Oral capsule / tea internal useLow

What is it

Calendula is a plant-derived ingredient sold as a dietary supplement and used in traditional herbal use. Found on roughly 803 U.S. supplement labels.

Is it worth it for you?

Use this as a quick fit check, not a diagnosis.

Worth considering if…

You're undergoing radiation therapy and your oncology team is open to a topical adjunct for skin reactions

You have minor non-infected skin abrasions, chapped lips, or mild inflammation and want a traditional topical option

You're managing chemotherapy-induced oral mucositis and your oncologist approves a herbal mouthwash trial

You're treating chronic venous leg ulcers as an adjunct to standard wound care and compression

You want a relatively gentle plant-based topical for minor sunburn or chapped skin

Probably skip if…

You have a known allergy to ragweed, chamomile, arnica, or other Asteraceae plants — risk of allergic dermatitis

You're trying to treat deep, infected, or surgical wounds — these need clinician-directed care, not herbal topicals

You're hoping oral calendula tea or capsules will reliably help internal conditions — the human evidence is weak

You're pregnant and considering oral use — uterine-stimulant concerns from traditional sources suggest avoiding internal use during pregnancy

Your wound or skin issue isn't improving in a few days — see a clinician rather than escalating self-treatment

Evidence at a glance

Goal	Effect	Best fit	Time
Radiation-induced dermatitis (topical prevention) Good Evidence	Reduction in grade ≥2 dermatitis from 63% (trolamine) to 41% (calendula) in the landmark Pommier trial	Adults receiving curative-intent radiotherapy (especially breast or head-and-neck) at risk of moderate-to-severe skin reactions	Days to weeks, with prophylactic use from the start of radiotherapy
Minor wound healing (topical) Limited Evidence	Greater wound-area reduction vs saline gauze in venous leg ulcers; supportive case-series evidence for minor wounds	Chronic venous leg ulcers (with compression therapy), minor cuts and abrasions, episiotomy healing	Days for minor abrasions; weeks for chronic ulcers
Chemotherapy- and radiation-induced oral mucositis Limited Evidence	Reduction in mucositis severity score over 21 days vs placebo in the Babaee trial	Adults with chemo- or radiation-induced oral mucositis seeking an adjunct to standard oral care (bland rinses, basic oral hygiene)	Days within a 2–3 week course
Oral or systemic use for internal conditions Mixed Evidence	No reliable RCT-grade effect for systemic indications	Traditional or culinary use as a tea or garnish — minimal expectation of clinical effect	Not established for systemic effect

Radiation-induced dermatitis (topical prevention)

Good Evidence

Effect: Reduction in grade ≥2 dermatitis from 63% (trolamine) to 41% (calendula) in the landmark Pommier trial
Best fit: Adults receiving curative-intent radiotherapy (especially breast or head-and-neck) at risk of moderate-to-severe skin reactions
Time: Days to weeks, with prophylactic use from the start of radiotherapy

Minor wound healing (topical)

Limited Evidence

Effect: Greater wound-area reduction vs saline gauze in venous leg ulcers; supportive case-series evidence for minor wounds
Best fit: Chronic venous leg ulcers (with compression therapy), minor cuts and abrasions, episiotomy healing
Time: Days for minor abrasions; weeks for chronic ulcers

Chemotherapy- and radiation-induced oral mucositis

Limited Evidence

Effect: Reduction in mucositis severity score over 21 days vs placebo in the Babaee trial
Best fit: Adults with chemo- or radiation-induced oral mucositis seeking an adjunct to standard oral care (bland rinses, basic oral hygiene)
Time: Days within a 2–3 week course

Oral or systemic use for internal conditions

Mixed Evidence

Effect: No reliable RCT-grade effect for systemic indications
Best fit: Traditional or culinary use as a tea or garnish — minimal expectation of clinical effect
Time: Not established for systemic effect

Evidence for 4 uses

AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.

Radiation-induced dermatitis (topical prevention)

Disease adjunct

Good Evidence

The single best-known trial is Pommier et al. 2004 (PMID 15084618): 254 women receiving postoperative breast irradiation were randomized to calendula ointment or trolamine. Acute dermatitis grade 2 or higher occurred in 41% of the calendula arm vs 63% of the trolamine arm (p<0.001), with less pain and fewer radiotherapy interruptions. The 2019 Givol systematic review of 8 RCTs (n=929) found Calendula generally non-inferior or modestly superior to comparators for radiation skin reactions, though formulation and comparator heterogeneity limit confidence. Standard radiation-oncology guidelines treat it as a reasonable option alongside aqueous cream or hydrogel dressings.

Effect size

Reduction in grade ≥2 dermatitis from 63% (trolamine) to 41% (calendula) in the landmark Pommier trial

Time to effect

Days to weeks, with prophylactic use from the start of radiotherapy

Best fit

Adults receiving curative-intent radiotherapy (especially breast or head-and-neck) at risk of moderate-to-severe skin reactions

Less likely

Patients on palliative radiotherapy with low expected skin toxicity; broken or weeping skin where ointment occlusion may worsen reaction

Bottom line: A reasonable topical option to discuss with your radiation oncology team — start before symptoms, use consistently. Not a replacement for the institution's standard skin-care protocol.

Evidence is mixed

Some replication trials have found no significant difference vs aqueous cream or other emollients; effect size depends on the comparator and the underlying skin care protocol. Cochrane reviews of radiation skin care don't single calendula out as superior.

SourceGivol et al., 2019 — Systematic review of Calendula for radiation dermatitis — PubMed — Phytother Res· conflicting Memorial Sloan Kettering Cancer Center — Calendula monograph — MSKCC About Herbs

SourcePommier et al., 2004 — Calendula vs trolamine for radiation dermatitis — PubMed — J Clin Oncol Givol et al., 2019 — Systematic review of Calendula for radiation dermatitis — PubMed — Phytother Res

Minor wound healing (topical)

Supplement benefit

Limited Evidence

Buzzi et al. 2016 (PMID 27523655) randomized 38 patients with chronic venous leg ulcers to twice-daily calendula cream or saline gauze for 30 weeks; the calendula arm had greater weekly wound-area reduction (7.4% vs 1.7%). Smaller trials and case series support topical calendula for episiotomy healing, diabetic foot ulcers as adjunct to standard care, and minor abrasions. The European Medicines Agency accepts calendula flower as a traditional herbal medicinal product for minor wounds and skin inflammation based on long-standing use.

Effect size

Greater wound-area reduction vs saline gauze in venous leg ulcers; supportive case-series evidence for minor wounds

Time to effect

Days for minor abrasions; weeks for chronic ulcers

Best fit

Chronic venous leg ulcers (with compression therapy), minor cuts and abrasions, episiotomy healing

Less likely

Deep or infected wounds, surgical sites, pressure ulcers requiring specialist wound care

Bottom line: Reasonable adjunct for minor wound care; don't use it as a substitute for proper wound dressings, debridement, or compression therapy for chronic ulcers.

SourceBuzzi et al., 2016 — Calendula cream for venous leg ulcers — PubMed — J Wound Care EMA — Community herbal monograph on Calendula officinalis L., flos — European Medicines Agency

Chemotherapy- and radiation-induced oral mucositis

Disease adjunct

Limited Evidence

Babaee et al. 2013 (PMID 23351340) randomized 40 patients with chemotherapy-induced oral mucositis to calendula mouthwash or placebo twice daily for 21 days; calendula reduced mucositis severity. Subsequent trials in head-and-neck radiotherapy patients have shown similar trends. MASCC/ISOO mucositis guidelines mention calendula among traditional options but don't formally recommend it.

Effect size

Reduction in mucositis severity score over 21 days vs placebo in the Babaee trial

Time to effect

Days within a 2–3 week course

Best fit

Adults with chemo- or radiation-induced oral mucositis seeking an adjunct to standard oral care (bland rinses, basic oral hygiene)

Less likely

Severe (grade 3–4) mucositis requiring IV opioid analgesia and clinician-directed therapy

Bottom line: Reasonable mouthwash adjunct if your oncologist agrees. Don't replace standard mucositis care (bland rinses, ice chips, opioid analgesia for severe cases).

SourceBabaee et al., 2013 — Calendula for chemo-induced oral mucositis — PubMed — Daru

Oral or systemic use for internal conditions

Mechanism only

Mixed Evidence

Calendula tea, tincture, and capsules are sold for digestion, menstrual support, immune support, and general inflammation. Human RCT evidence for internal use is sparse to absent. The European Medicines Agency accepts oral preparations for minor inflammations of the mouth and throat (a mucosal application via rinsing), but not for systemic indications. Mechanism-only claims for liver, gallbladder, or hormonal benefit don't have controlled trial support.

Effect size

No reliable RCT-grade effect for systemic indications

Time to effect

Not established for systemic effect

Best fit

Traditional or culinary use as a tea or garnish — minimal expectation of clinical effect

Less likely

Anyone seeking measurable systemic benefit (digestion, hormones, immunity) — choose better-studied botanicals

Bottom line: Calendula's evidence is on the skin and mucosa, not from swallowing it. Save your money for the topical preparations.

SourceMemorial Sloan Kettering Cancer Center — Calendula monograph — MSKCC About Herbs EMA — Community herbal monograph on Calendula officinalis L., flos — European Medicines Agency

How it works

Calendula contains a mixture of plant compounds, and the exact mechanism behind any effects depends on the specific preparation, the part of the plant used, and how it is extracted. Concentrations of active constituents can vary substantially between products. Most botanical effects are studied as a whole-plant or extract effect rather than tied to a single isolated molecule. Without strong human trial data, claims about how Calendula works should be treated cautiously.

How to take it

1. Typical dose

• Topical ointment or cream (2–5% calendula): apply 2–3 times daily to clean, intact or partially intact skin • Mouthwash: calendula tincture 2% diluted in water, swish 2× daily for oral mucositis • Tea (traditional internal use, mouth/throat application only): 1–2 g dried flowers in 150 mL hot water, 2–3 times daily as a gargle

2. Higher studied dose

Pommier 2004 used calendula ointment at least twice daily throughout radiotherapy. No standard 'oral' dose exists for systemic indications — internal use is largely traditional, not dose-validated by RCTs.

3. Timing

Topical: apply after cleansing the area. For radiation skin care, start before any symptoms appear and apply consistently; check with your radiation oncology team about timing relative to treatment sessions (some institutions ask you not to apply within 2 hours before radiotherapy).

4. With food

Topical use — not applicable. Oral mouthwash use is independent of meals.

5. Split dosing

Topical applications split 2–3 times daily provide better wound contact than single daily use. Mouthwash 2–3× daily mirrors the trial protocols.

6. How long to try

Topical wound or skin use: continue until the skin is fully healed or for the duration of radiotherapy (typically 5–7 weeks for breast cancer). Re-evaluate any wound or rash that hasn't improved within 1–2 weeks.

What to track

Skin reaction grade if using during radiotherapy (your oncology nurse will score this)

Wound size and characteristics (photograph weekly if chronic)

Any new redness, itching, or rash — could indicate Asteraceae allergic dermatitis (stop and reassess)

Pain or oral comfort if using as a mucositis mouthwash

Bottom line: Use it topically, start before problems escalate, apply consistently. Discuss with your oncology team if using during cancer treatment.

6 commercial forms

Compare the main delivery options and what they’re best suited for.

Calendula ointment / cream (topical)

Most-studied

Petrolatum or lanolin-based ointment containing 2–10% calendula extract. The form used in the Pommier 2004 radiation dermatitis trial and most clinical research. Best for skin reactions, minor wounds, and chapped skin.

Topical delivery; clinical evidence is on this form.

Calendula oil (infused)

Traditional carrier

Olive or sunflower oil infused with calendula flowers, used as a massage oil, hair treatment, or DIY ointment base. Lower active concentration than commercial ointments; appropriate for routine skin care, not for therapeutic wound treatment.

Lower potency than concentrated ointments.

Calendula tincture

Alcohol extract

Alcoholic extract of calendula flowers (typically 1:5 ratio), used as a base for mouthwash dilutions or topical compress. Alcohol stings broken skin — dilute heavily for wound use.

Use diluted; sting risk on broken skin.

Calendula mouthwash (diluted tincture)

For oral mucositis

2% calendula tincture in water, swished 2–3× daily. The form used in the Babaee 2013 oral mucositis trial.

Local mucosal delivery for oral/throat use.

Calendula tea / dried flowers

Traditional internal use

1–2 g dried flowers in 150 mL hot water. Traditional use as a mouth/throat gargle (mucosal contact). Internal swallowed use lacks RCT support for any systemic indication.

Internal use unsupported by controlled trials.

Calendula capsules / extract (oral)

Limited evidence

Encapsulated dried herb or standardized extract. Sold for digestive, menstrual, or immune indications without controlled human trials. Save your money — the evidence is on topical formulations.

Systemic use unsupported.

Safety

Know the common side effects, key cautions, and who should avoid it.

Common side effects

mild local irritation (uncommon)allergic contact dermatitis in Asteraceae-sensitive individuals

Serious risks

Allergic contact dermatitis in people sensitized to ragweed, chamomile, arnica, or other Asteraceae/Compositae plants — patch-test a small area first if you have any of these allergies.
SourcePaulsen, 2002 — Contact allergy to Compositae plants — PubMed — Contact Dermatitis Memorial Sloan Kettering Cancer Center — Calendula monograph — MSKCC About Herbs
Topical application to deep, weeping, or infected wounds can occlude the wound bed and worsen infection — these wounds need clinician-directed care, not herbal occlusive ointments.
SourceMemorial Sloan Kettering Cancer Center — Calendula monograph — MSKCC About Herbs

Who should avoid it

People with known allergy to plants in the Asteraceae/Compositae family (ragweed, daisies, chamomile, arnica, marigolds).
SourcePaulsen, 2002 — Contact allergy to Compositae plants — PubMed — Contact Dermatitis
Anyone using it to treat deep wounds, surgical sites, or burns greater than minor first-degree — clinician-directed wound care is required.
SourceMemorial Sloan Kettering Cancer Center — Calendula monograph — MSKCC About Herbs
Pregnant women considering oral / internal use — traditional sources cite uterine-stimulant concerns and there are no RCTs establishing safety in pregnancy. Topical use for minor skin issues is generally considered acceptable.
SourceEMA — Community herbal monograph on Calendula officinalis L., flos — European Medicines Agency

Pregnancy & breastfeeding

Topical calendula for minor skin issues is generally considered low-risk in pregnancy. Oral / internal use during pregnancy is traditionally avoided because of uterine-stimulant concerns cited in older herbal sources, and there are no RCTs establishing pregnancy safety. The European Medicines Agency recommends against internal use during pregnancy and breastfeeding in the absence of safety data.

SourceEMA — Community herbal monograph on Calendula officinalis L., flos — European Medicines Agency Memorial Sloan Kettering Cancer Center — Calendula monograph — MSKCC About Herbs

Bottom line: Well tolerated topically by most people. Skip if you have ragweed-family allergies, treat only minor non-infected wounds, and avoid internal use during pregnancy.

Interactions

sedative medications (CNS depressants)Minor

Animal studies suggest calendula may have mild sedative effects, theoretically additive with benzodiazepines, opioids, alcohol, or sleep aids. Clinical significance in topical use is negligible; relevance is to high-dose oral use.

SourceMemorial Sloan Kettering Cancer Center — Calendula monograph — MSKCC About Herbs

antihypertensivesMinor

Animal and small human data suggest calendula may modestly lower blood pressure; theoretical additive effect with antihypertensive drugs. Topical use poses no meaningful concern.

SourceMemorial Sloan Kettering Cancer Center — Calendula monograph — MSKCC About Herbs

blood sugar lowering medications (diabetes drugs)Minor

Preliminary in vitro and animal data suggest calendula may have hypoglycemic effects; relevance to oral human use is unconfirmed and topical use is not a concern.

SourceMemorial Sloan Kettering Cancer Center — Calendula monograph — MSKCC About Herbs

Choosing a product

What to look for on the label — and what to be skeptical of.

Look for…

Topical preparations should state the calendula extract concentration (e.g., 2%, 5%, 10%) and the carrier (ointment, cream, oil, hydrogel)

Look for standardized extracts from Calendula officinalis (not C. arvensis or unrelated 'marigold' species like Tagetes)

Manufacturer with certificate of analysis (COA) — verifies plant identity and absence of contaminants

For radiation dermatitis use, choose an ointment or cream base rather than alcohol-based tincture (alcohol stings broken skin)

Hypoallergenic formulations without added fragrance reduce contact dermatitis risk

Be skeptical of…

Oral capsules marketed for liver detox, hormone balance, or immune support — no controlled human evidence for systemic use

Anti-cancer claims for calendula tea or extract — completely unsupported by RCTs

Antiviral claims for topical use beyond minor inflammation — herpes simplex and other claims lack reliable human evidence

'Marigold' products that don't clarify whether they are Calendula officinalis or Tagetes (a different genus with different chemistry)

Frequently asked questions

What is Calendula used for?⌄

Calendula is used traditionally for various supportive purposes. Human evidence for specific health claims is generally limited, so it is best treated as a complementary option rather than a treatment.

Is Calendula safe?⌄

Calendula is generally well tolerated at typical doses, but quality varies between products. People who are pregnant, breastfeeding, taking prescription medications, or managing a medical condition should check with a healthcare provider first.

How long does it take to work?⌄

Effects of botanical supplements often take several weeks of consistent use, if they appear at all. Reassess after 8-12 weeks of regular use.

References by claim

Radiation-induced dermatitis (topical prevention)

Pommier et al., 2004 — Calendula vs trolamine for radiation dermatitis — PubMed — J Clin Oncol (2004) link

Memorial Sloan Kettering Cancer Center — Calendula monograph — MSKCC About Herbs (2024) link

Givol et al., 2019 — Systematic review of Calendula for radiation dermatitis — PubMed — Phytother Res (2019) link

Minor wound healing (topical)

Buzzi et al., 2016 — Calendula cream for venous leg ulcers — PubMed — J Wound Care (2016) link

EMA — Community herbal monograph on Calendula officinalis L., flos — European Medicines Agency (2018) link

Chemotherapy- and radiation-induced oral mucositis

Babaee et al., 2013 — Calendula for chemo-induced oral mucositis — PubMed — Daru (2013) link

Safety

Paulsen, 2002 — Contact allergy to Compositae plants — PubMed — Contact Dermatitis (2002) link

Other references

Calendula officinalis on Wikidata — Wikidata link

Track Calendula with Pilora

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Evidence-based·Last reviewed Jun 1, 2026·Evidence current as of Jun 1, 2026·How we grade evidence

Disclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.