Chamomile mouthwash for treatment-related oral mucositis

Evidence label: Mixed / uncertain · Clinical goal: prevent or reduce chemotherapy- or transplant-associated mouth sores

Evidence at a glance

Population: people receiving 5-fluorouracil chemotherapy or allogeneic stem-cell transplantation.
Intervention: short-term chamomile mouthwash or topical chamomile preparations; formulations and concentrations varied.
Result: a 164-person placebo-controlled trial was negative, while smaller later studies and a nonrandomized cohort reported signals.

What was studied

The largest direct trial randomized 164 evaluable patients receiving 5-fluorouracil to chamomile or placebo mouthwash three times daily for 14 days; it did not support the prespecified hypothesis.

A 40-person phase II transplant study compared 0.5%, 1% and 2% liquid-extract mouthwashes with standard care. Later small trials studied a topical gel, and a 2025 prospective supportive-care cohort reported oral mucositis in 5.4% with chamomile versus 26.5% in controls (P=.016).

What the evidence shows

The most reliable-sized placebo-controlled study was negative. Later signals come from smaller dose-finding trials, topical formulations or an observational cohort, so they do not overturn that result.

Chamomile may be reasonable to study as a low-burden oral-care adjunct, but it is not an established substitute for protocol-based oral hygiene, pain control, nutrition support or guideline-supported mucositis prevention.

Limits and uncertainty

Chamomile species, extraction method, concentration, vehicle, chemotherapy and outcome grading differ. The 2025 cohort was not randomized and is vulnerable to selection and supportive-care differences.

Several sources were appraised from abstracts. Exact product chemistry, funding and all adverse-event denominators were not verified.

Safety and practical context

Chamomile can cause allergic reactions, including rare anaphylaxis—especially in people allergic to ragweed, chrysanthemums, marigolds or daisies. NCCIH also notes reported interactions with warfarin and some liver-metabolized medicines.

Use an alcohol-free, nonirritating preparation if the oncology team approves. New fever, inability to drink, bleeding, severe pain or suspected infection needs prompt clinical assessment.

Questions for the care team

Which chamomile species, concentration and solvent does the product contain?
Do I have a ragweed-family allergy or take warfarin or another interaction-sensitive medicine?
What standard oral-care and pain plan continues alongside it?

Sources

Literature searched: October 15, 2026 · Record appraised: October 15, 2026

Educational evidence summary, not personal medical advice. Research regimens describe what was studied; they are not personal prescribing instructions and should not replace cancer treatment or individualized supportive care.