CalendulaBotanical

• Minor wounds (topical)Possibly helps

  A systematic review of 14 studies (7 animal, 7 clinical) found acute wound models resolved their inflammatory phase faster and built more granulation tissue with calendula extract [3].
  
  The same reviewers describe the overall human efficacy evidence as inconclusive. Acute wounds look far better than chronic ones. ^[3]

• Chronic leg ulcersPossibly helps

  Two controlled studies in venous leg ulcers reported reduced ulcer area versus control [3].
  
  A randomized trial in diabetic leg ulcers found no improvement at all [3]. Same plant, opposite result, different wound type. ^[3]

• BurnsPossibly helps

  A randomized trial in partial- and full-thickness burns found no benefit over control [3].
  
  Some animal work points the other way, which is why the reviewers left burns unresolved rather than negative [3]. ^[3]

• Radiation dermatitisPossibly helps

  The largest controlled result calendula has: a phase III trial in 254 breast-cancer patients undergoing radiotherapy found calendula ointment reduced acute radiation dermatitis versus trolamine cream [12].
  
  That is one trial, not a body of evidence — which is why this sits at unclear rather than settled. ^[12]

• Post-surgical woundsPossibly helps

  Randomized trials report calendula ointment speeding recovery of episiotomy, perineal and post-cesarean wounds [12].
  
  These are positive results in acute surgical wounds, the setting where calendula consistently does best. ^[12]

• Where the disagreement sitsPossibly helps

  ⚠ Regulators and trialists are not saying the same thing, and we are not resolving it for you.
  
  Health Canada, the EMA's HMPC, German Commission E and ESCOP all endorse calendula on traditional use grounds [5].
  
  The systematic review that pooled the actual human trials calls the efficacy evidence inconclusive, because chronic-wound and burn trials contradict the acute-wound ones [3]. ^[3]

• What is doing the workPossibly helps

  Preclinical work attributes calendula's anti-inflammatory, antioxidant, antimicrobial and wound-repair activity mainly to triterpenoid esters [1].
  
  Faradiol monoesters are considered the main anti-inflammatory constituents, alongside flavonoids [1]. This is laboratory-level attribution, not clinical evidence. ^[1]

• Topical semi-solids (cream, gel, ointment, salve)The only route with a government monograph behind it

  Elemental content

  2–20% dried flower, or 5–10% tincture/fluid extract

  Absorption

  Applied to the affected area as needed; Health Canada also recognizes solution and spray forms

  Best for

  The only route with a government monograph behind it [5]

• Liquid compressLarger or awkwardly shaped patches of irritated skin

  Elemental content

  Decoction or infusion at 90–100% extract; tincture or fluid extract at 1–100%

  Absorption

  A tincture compress is typically diluted 1 part extract to 3 parts warm water, changed several times a day

  Best for

  Larger or awkwardly shaped patches of irritated skin [5]

• Oral tea, tincture, fluid extractTraditional oral use. Far less clinically tested than topical calendula, and no government monograph covers it

  Elemental content

  Tincture 1:2 to 1:5, fluid extract 1:1, infused oil 1:10, decoction/infusion 1–2 g dried flower per 150–250 mL water

  Absorption

  Capsules and tablets from standardized hydroethanolic extract also exist in the formulation literature

  Best for

  Traditional oral use. Far less clinically tested than topical calendula, and no government monograph covers it [6]

• Culinary petalsColor and a faintly bitter note in salads, soups, stews and cheese

  Elemental content

  Fresh or dried ray florets, unstandardized

  Absorption

  Only the petals are used, not the whole flower head

  Best for

  Color and a faintly bitter note in salads, soups, stews and cheese [10]

• Reported side effects

  Side effects are described as uncommon, and are mainly allergic reactions in already-sensitized people [7].
  
  No source reviewed here documents organ toxicity from ordinary topical use [6]. ^[7]

• Asteraceae cross-allergy

  Calendula sits in the Asteraceae/Compositae family with ragweed, chrysanthemums and daisies, and drug references list Asteraceae hypersensitivity as a contraindication [6].
  
  Asteraceae species are a recognized cause of type IV delayed hypersensitivity contact reactions, via sesquiterpene lactones [11].
  
  EU herbal-medicine regulation requires every Asteraceae herbal product to carry a contraindication for hypersensitivity to other plants in the family, not just the one used [11]. ^[11]

• Pregnancy and breastfeeding

  Oral calendula is discouraged in pregnancy: limited animal data suggest it may cause uterine contractions and raise miscarriage risk [8].
  
  Topical safety data in pregnancy are considered insufficient, so consumer sources advise avoiding both routes [8].
  
  Health Canada requires topical products to carry the label caution to ask a health care practitioner before use if you are pregnant [5]. ^[5]

• Sedatives and CNS depressants

  A supplement-interaction checker rates calendula with sedative and CNS-depressant medicines as a moderate interaction, on added-drowsiness grounds [7].
  
  The same source advises stopping calendula at least two weeks before scheduled surgery, because of possible excess sedation with anesthesia-related drugs [7]. ^[7]

• One source, two answers

  ⚠ RxList contradicts itself here, and we are showing both halves.
  
  Its generic-drug page says calendula has no known severe, serious, moderate or mild drug interactions [6]. Its supplement-interaction checker rates the sedative interaction as moderate [7]. ^[6]

Calendula is the food itself, not a nutrient found across foods.

Fresh petals go into salads and garnishes; dried petals add a yellow-orange color and a slightly bitter note to soups, stews and cheese [10].

It is commonly used as a cheap stand-in for saffron's color — it does not deliver saffron's flavor [10].

No source reviewed here specifies a time of day, or with food versus without [5][6].

That is not an oversight: calendula is mostly a topical product, applied to the affected area whenever it is needed [5].

The oral forms are all suggested as three times daily, split across the day rather than tied to morning or bedtime [6][8].