Chamomile is a flowering plant in the daisy family (Asteraceae) whose dried flower heads are brewed as tea and sold as extracts and capsules. The plant most studied, and the one this page covers, is German chamomile (Matricaria recutita, also called Matricaria chamomilla). It is promoted for sleep, anxiety, digestion, colds and skin or mouth irritation (NCCIH).
The single most important fact is that the evidence is thin. The US National Center for Complementary and Integrative Health (NCCIH) states that studies “have not produced sufficient reliable evidence to rate clinical usefulness.” The best human data are small trials in generalized anxiety disorder (GAD) and mixed results for sleep. In the EU, chamomile medicines are registered on the basis of traditional use, not proven efficacy (EMA).
This page summarizes what clinical trials, meta-analyses and regulators report. It is for education only and is not medical advice.
| Property | Detail |
|---|---|
| Type | Herbal product (dried flower heads, tea, extracts) |
| Main species | German chamomile, Matricaria recutita L.; Roman chamomile is a different plant (Anthemis nobilis, also called Chamaemelum nobile) |
| Route | Oral (tea, capsules); also mouth rinse, skin, inhalation |
| EU traditional tea dose (adults) | 1.5–4 g dried flower in 150 mL boiling water, 3–4 times daily (EMA monograph) |
| Doses in trials | Extract 220–1,100 mg/day (GAD, 8 weeks); 1,500 mg/day (GAD, up to 38 weeks); 540 mg/day (insomnia, 28 days) |
| Half-life | No human plasma half-life published for chamomile constituents; after chamomile tea, the main apigenin metabolite peaked at about 2 h |
| Proposed mechanism | Apigenin binds the benzodiazepine site of the GABA-A receptor in lab studies (mice and receptor assays) |
| US status | Sold as a dietary supplement (not FDA-approved for any disease); listed as generally recognized as safe (GRAS) as a food flavoring |
| WADA status | Not named on the 2026 Prohibited List |
What it is
German chamomile flowers contain flavonoids, mainly apigenin and its sugar-bound forms (glycosides), plus an essential oil with compounds such as chamazulene and α-bisabolol (Zick et al., BMC Complement Altern Med 2011; Ganzera et al., Life Sci 2006). Products differ widely in how much of each they contain, which makes trials hard to compare.
Chamomile has been used as a medicinal herb since antiquity, in ancient China, Egypt, Greece and Rome (NCCIH). Two different plants are both sold as “chamomile.” The US food regulations list them separately:
| Common name | Botanical name | US food listing |
|---|---|---|
| German or Hungarian chamomile | Matricaria chamomilla L. | GRAS spice/flavoring and GRAS flower extract or essential oil |
| English or Roman chamomile | Anthemis nobilis L. | GRAS spice/flavoring and GRAS flower extract or essential oil |
Sources: 21 CFR 182.10; 21 CFR 182.20.
Proposed mechanism
The calming effect is usually attributed to apigenin. In a 1995 lab study, apigenin isolated from chamomile flowers bound the central benzodiazepine receptor (the same site that drugs like diazepam act on) with a Ki of 4 µM. In mice, it reduced anxiety-like behavior without sedation or muscle relaxation at lower doses, and caused mild sedation at a 10-fold higher dose (Viola et al., Planta Med 1995). Whether the amounts absorbed from tea or capsules act the same way in people has not been shown.
How it works in the body
Human absorption data are limited. In a study of healthy men, apigenin taken on its own was poorly absorbed: metabolites equal to only 0.5% of the dose appeared in urine over 24 hours. After chamomile tea, which supplies apigenin as a glycoside (apigenin-7-O-glucoside), absorption was much better (Borges et al., Free Radic Biol Med 2022):
| Measure (chamomile tea) | Result |
|---|---|
| Main circulating form | Apigenin-4’-glucuronide (a liver/gut conjugate, not free apigenin) |
| Time to peak plasma level | About 2 h, consistent with absorption in the upper gut |
| Urinary excretion of apigenin metabolites | Equal to 34% of apigenin intake |
No study we could find reports an elimination half-life for chamomile constituents in humans. The EMA monograph states that pharmacokinetic data were not required for its traditional-use assessment (EMA monograph).
Regulatory status
- United States: chamomile products sold for oral use are generally marketed as dietary supplements, which FDA does not approve before sale (NCCIH). Both German and Roman chamomile are GRAS as food flavorings (21 CFR 182.10; 21 CFR 182.20). It is not a controlled substance.
- European Union: the EMA’s herbal committee (HMPC) adopted a monograph in July 2015 that supports traditional-use registration. HMPC concluded that clinical trial data were insufficient to count as evidence, so the uses rest on at least 30 years of safe traditional use (EMA).
- Sport: chamomile is not named on the WADA 2026 Prohibited List. As with any supplement, the list does not vouch for what a given product actually contains.
EU traditional uses
The EMA monograph lists these traditional uses for chamomile flower medicines:
- symptoms of minor gastrointestinal complaints such as bloating and minor spasms;
- symptoms of the common cold (as a steam inhalation);
- minor ulcers and inflammation of the mouth and throat;
- add-on treatment of skin irritation around the anus and genitals, after a doctor has excluded serious conditions;
- minor skin inflammation (sunburn), superficial wounds and small boils.
| Group (oral tea, digestive use) | Single dose | Times per day |
|---|---|---|
| Adolescents, adults, elderly | 1.5–4 g in 150 mL boiling water | 3–4 |
| Children 6–12 years | 1.5–3.0 g | 2–4 |
| Children 2–6 years | 1.0–1.5 g | 2–4 |
| Children 6 months–2 years | 0.5–1.0 g | 2–4 |
Source: EMA monograph. The monograph advises seeing a doctor if symptoms last more than one week.
What the research shows
Generalized anxiety disorder
The strongest data come from one research group at the University of Pennsylvania.
Short-term trial. In a randomized, double-blind, placebo-controlled trial, 57 outpatients with mild to moderate GAD took a German chamomile extract standardized to 1.2% apigenin (220 mg capsules) or placebo for 8 weeks. The dose started at 1 capsule a day and rose to as many as 5 (220–1,100 mg/day) in patients who had not improved by half (Amsterdam et al., J Clin Psychopharmacol 2009):
| Outcome | Chamomile (n = 28) | Placebo (n = 29) | p |
|---|---|---|---|
| Hamilton Anxiety Rating (HAM-A) total, difference in change | −3.17 points vs placebo (95% CI −6.29 to −0.45) | Reference | 0.047 |
| HAM-A responders (at least 50% reduction) | 57% | 38% | 0.146 |
| Percentage change in HAM-A | −53% | −35% | 0.085 |
| Stopped for adverse events | 1 patient | 1 patient | Not reported |
The primary result was barely significant, and no secondary outcome reached significance. The authors described the effect as “modest.”
Long-term trial. A later study gave 179 people with moderate to severe GAD open-label chamomile extract 1,500 mg/day (500 mg three times daily) for 12 weeks. The 93 responders were then randomized to 26 more weeks of chamomile or placebo (Mao et al., Phytomedicine 2016):
| Outcome (randomized phase) | Chamomile (n = 46) | Placebo (n = 47) |
|---|---|---|
| Relapsed | 15.2% | 25.5% |
| Mean time to relapse | 11.4 weeks | 6.3 weeks |
| Hazard ratio for relapse | 0.52 (95% CI 0.20–1.33; p = 0.16, not significant) | Reference |
The primary outcome, relapse, was not significantly reduced. GAD symptom scores stayed significantly lower on chamomile (p = 0.0032), and body weight and mean arterial blood pressure were also significantly lower. Adverse event rates were low and similar in both groups.
A 2019 meta-analysis pooled the GAD data and found HAM-A improvements of 1.43 points at 2 weeks (95% CI −2.47 to −0.39) and 1.79 points at 4 weeks (95% CI −3.14 to −0.43). For state anxiety (short-term anxiety in people without GAD), three trials showed no effect (SMD −0.15, 95% CI −0.46 to 0.16) (Hieu et al., Phytother Res 2019). NCCIH describes the GAD results as preliminary (NCCIH).
Sleep and insomnia
Chamomile is widely used for sleep, but the evidence for diagnosed insomnia is weak.
- Chronic insomnia: a pilot randomized, double-blind trial gave 34 adults with primary insomnia 270 mg of a standardized extract twice daily or placebo for 28 days. There were no significant differences in total sleep time, sleep efficiency, time to fall asleep, waking after sleep onset, sleep quality or number of awakenings. Total sleep time showed a moderate effect size in favor of placebo (Zick et al., BMC Complement Altern Med 2011).
- Postnatal women: in a trial of 80 Taiwanese women with poor sleep after childbirth, 2 weeks of chamomile tea improved physical-symptom-related sleep inefficiency and depression scores versus usual care. The control group got no placebo, and the differences had disappeared 4 weeks after the tea was stopped (Chang and Chen, J Adv Nurs 2016).
| Meta-analysis | Studies | Main finding |
|---|---|---|
| Hieu et al. 2019 | 12 randomized trials | Sleep quality improved (SMD −0.73, 95% CI −1.23 to −0.23); only one insomnia trial, with no change in insomnia severity |
| Kazemi et al. 2024 | 10 studies, 772 participants | Pittsburgh Sleep Quality Index improved by 1.88 points (95% CI −3.46 to −0.31), with very high heterogeneity (I² 88.4%); no improvement in sleep duration, sleep efficiency or daytime functioning |
The 2024 review noted that only one included study checked whether blinding worked and tested the product’s purity or potency. Most outcomes were self-reported rather than measured objectively.
Blood sugar
A 2024 meta-analysis found 4 human randomized trials in which chamomile lowered fasting blood glucose (SMD −0.65, 95% CI −1.00 to −0.29) and HbA1c (SMD −0.90, 95% CI −1.39 to −0.40). The authors called for more trials to confirm this (Akhgarjand et al., J Diabetes Metab Disord 2024). Standardized mean differences do not translate directly into mg/dL or percentage points.
Other uses
NCCIH notes that small studies suggest chamomile mouthwashes may help prevent or treat mouth inflammation (mucositis) after radiation, chemotherapy or stem cell transplantation. Studies in infant colic and children’s diarrhea used multi-herb products, so chamomile’s own role is unclear (NCCIH). No controlled human trials show effects on muscle growth, testosterone or athletic performance.
Side effects and risks
Overall tolerability
NCCIH considers chamomile likely safe in amounts found in teas and foods, and possibly safe for short-term medicinal use. Side effects are uncommon and may include nausea, dizziness and allergic reactions (NCCIH).
A 2025 systematic review found 72 clinical trials in which 2,896 patients received chamomile. Only 65 adverse events were reported across 10 trials, mostly mild gastrointestinal complaints and drowsiness. However, 28 trials gave no adverse event data at all, so true rates are uncertain (Ostovar et al., Complement Ther Med 2025).
Allergy and anaphylaxis
Allergic reactions are the main documented serious risk.
- The EMA monograph lists hypersensitivity, including severe reactions such as breathing difficulty, angioedema, circulatory collapse and anaphylactic shock, after mucosal contact with liquid chamomile preparations. Their frequency is not known (EMA monograph).
- Among 11 case reports in the 2025 review, 6 involved allergic reactions, including anaphylaxis in 3 patients (Ostovar et al. 2025).
- In an Austrian series of 14 patients sensitized to chamomile, 10 had a history of immediate-type reactions, some life-threatening. Most were also sensitized to mugwort pollen, and several to birch pollen (Reider et al., Clin Exp Allergy 2000).
People allergic to related plants such as ragweed, chrysanthemums, marigolds or daisies are more likely to react (NCCIH). The EMA contraindicates chamomile in anyone allergic to it or to other plants of the Asteraceae family.
Interactions
- Warfarin: a 70-year-old woman on warfarin was hospitalized with multiple internal hemorrhages after using chamomile tea and skin lotion (Segal and Pilote, CMAJ 2006). NCCIH lists warfarin among drugs with reported interactions.
- Liver-metabolized drugs: in a lab study, chamomile essential oil and its constituents inhibited the drug-metabolizing enzymes CYP1A2 (most strongly), CYP3A4, CYP2C9 and CYP2D6 in vitro (Ganzera et al., Life Sci 2006). The EMA monograph notes CYP450-related interactions reported in kidney transplant patients taking high oral doses for about two months.
- Sedatives: NCCIH notes a theoretical risk of interaction with sedative drugs.
- Hormonal effects: NCCIH states that chamomile might have estrogen-like effects, that preliminary studies suggest it might reduce the effect of birth control pills, and that it might worsen estrogen-sensitive conditions such as breast or uterine cancer.
Pregnancy and breastfeeding
NCCIH says little is known about safety in pregnancy or breastfeeding. The EMA monograph states that safety in pregnancy and lactation has been established for the dried, cut flower (the form used for tea), but does not recommend the extract preparations in pregnancy or lactation because data are lacking. The 2025 safety review also found insufficient pregnancy and lactation data.
Quality and product variability
Chamomile supplements are not standardized to a single specification. The insomnia trial’s product was labeled at 2.5 mg or more of apigenin per tablet, but laboratory testing during the study found 3.9 mg apigenin per 90 mg of extract (Zick et al. 2011). The GAD trials standardized to 1.2% apigenin. Results from one product may not apply to another, or to tea.
Key takeaways
- A traditional herb with limited proof. NCCIH says the evidence is not sufficient to rate clinical usefulness, and EU registration rests on traditional use, not trials.
- Modest signal in anxiety. One 57-person trial found a small, barely significant HAM-A benefit; a longer trial did not significantly reduce relapse.
- Mixed results for sleep. Self-rated sleep quality improved in meta-analyses, but the only insomnia trial found no benefit and sleep duration did not change.
- Allergy is the main serious risk. Anaphylaxis has been reported, especially in people sensitized to mugwort, ragweed or other daisy-family plants.
- Interactions are documented. A warfarin bleeding case, in-vitro CYP inhibition and EMA-noted reports in transplant patients point to possible interactions with blood thinners and liver-metabolized drugs.
- No anabolic or performance effects shown. There are no human trials on muscle, hormones or sport performance; it is not on the WADA list.
Sources
- National Center for Complementary and Integrative Health. Chamomile: usefulness and safety. NCCIH.
- Committee on Herbal Medicinal Products. European Union herbal monograph on Matricaria recutita L., flos. EMA/HMPC/55843/2011. Adopted July 7, 2015. EMA.
- European Medicines Agency. Matricariae flos: herbal medicinal product (summary for the public, EMA/490629/2015). EMA.
- Spices and other natural seasonings and flavorings. 21 CFR 182.10. eCFR.
- Essential oils, oleoresins (solvent-free), and natural extractives (including distillates). 21 CFR 182.20. eCFR.
- World Anti-Doping Agency. World Anti-Doping Code International Standard: Prohibited List 2026. WADA 2026 Prohibited List.
- Viola H, Wasowski C, Levi de Stein M, et al. Apigenin, a component of Matricaria recutita flowers, is a central benzodiazepine receptors-ligand with anxiolytic effects. Planta Med. 1995;61(3):213–216. PubMed.
- Borges G, Fong RY, Ensunsa JL, et al. Absorption, distribution, metabolism and excretion of apigenin and its glycosides in healthy male adults. Free Radic Biol Med. 2022;185:90–96. PubMed.
- Amsterdam JD, Li Y, Soeller I, et al. A randomized, double-blind, placebo-controlled trial of oral Matricaria recutita (chamomile) extract therapy for generalized anxiety disorder. J Clin Psychopharmacol. 2009;29(4):378–382. PubMed; PMC.
- Mao JJ, Xie SX, Keefe JR, et al. Long-term chamomile (Matricaria chamomilla L.) treatment for generalized anxiety disorder: a randomized clinical trial. Phytomedicine. 2016;23(14):1735–1742. PubMed.
- Zick SM, Wright BD, Sen A, Arnedt JT. Preliminary examination of the efficacy and safety of a standardized chamomile extract for chronic primary insomnia: a randomized placebo-controlled pilot study. BMC Complement Altern Med. 2011;11:78. PubMed; PMC.
- Chang SM, Chen CH. Effects of an intervention with drinking chamomile tea on sleep quality and depression in sleep disturbed postnatal women: a randomized controlled trial. J Adv Nurs. 2016;72(2):306–315. PubMed.
- Hieu TH, Dibas M, Surya Dila KA, et al. Therapeutic efficacy and safety of chamomile for state anxiety, generalized anxiety disorder, insomnia, and sleep quality: a systematic review and meta-analysis of randomized trials and quasi-randomized trials. Phytother Res. 2019;33(6):1604–1615. PubMed.
- Kazemi A, Shojaei-Zarghani S, Eskandarzadeh P, Hashempur MH. Effects of chamomile (Matricaria chamomilla L.) on sleep: a systematic review and meta-analysis of clinical trials. Complement Ther Med. 2024;84:103071. PubMed.
- Akhgarjand C, Moludi J, Ebrahimi-Mousavi S, et al. The effect of chamomile consumption on glycemic markers in humans and animals: a systematic review and meta-analysis. J Diabetes Metab Disord. 2024;23(1):189–198. PubMed.
- Ostovar M, Rezaee Z, Najibi SM, Hashempur MH. Chamomile: a systematic review of adverse events. Complement Ther Med. 2025;91:103192. PubMed.
- Reider N, Sepp N, Fritsch P, et al. Anaphylaxis to camomile: clinical features and allergen cross-reactivity. Clin Exp Allergy. 2000;30(10):1436–1443. PubMed.
- Segal R, Pilote L. Warfarin interaction with Matricaria chamomilla. CMAJ. 2006;174(9):1281–1282. PubMed.
- Ganzera M, Schneider P, Stuppner H. Inhibitory effects of the essential oil of chamomile (Matricaria recutita L.) and its major constituents on human cytochrome P450 enzymes. Life Sci. 2006;78(8):856–861. PubMed.