Chamomile (Matricaria chamomilla)

Matricaria chamomilla / recutita
Evidence Level
Moderate
2 Clinical Trials
5 Documented Benefits
3/5 Evidence Score

Chamomile is one of the most widely consumed herbal teas globally and among the oldest documented medicinal plants — appearing in ancient Egyptian, Greek, and Roman pharmacopeias. Its flower extract contains apigenin, bisabolol, and chamazulene — compounds with well-characterized anxiolytic, anti-inflammatory, antispasmodic, and sleep-promoting properties. Clinical trials now validate chamomile's traditional reputation for anxiety, insomnia, and digestive comfort.

Studied Dose 270–1,500 mg/day dried flower extract; anxiety: 500 mg–1,500 mg/day standardized extract; tea: 1–4 cups/day (1–2g dried flowers per cup); sleep: 270 mg twice daily
Active Compound Apigenin (flavonoid, GABA-A receptor modulator), alpha-bisabolol, chamazulene, and apigenin-7-glucoside — standardized extract typically 1.2% apigenin

Generalized anxiety disorder reduction

A landmark Penn Medicine RCT demonstrated chamomile extract (1,500 mg/day) significantly reduced GAD symptom scores on the Hamilton Anxiety Rating Scale vs. placebo over 8 weeks — the first large, well-designed RCT establishing chamomile as a clinically meaningful natural anxiolytic. Long-term use (26 weeks) reduced relapse risk by 56% vs. placebo withdrawal.

Sleep quality and insomnia improvement

Multiple clinical studies confirm chamomile improves sleep quality, reduces time to fall asleep, and improves next-day functioning in adults with insomnia and sleep disturbances. Apigenin's GABA-A receptor binding produces sedative effects without the dependency or rebound insomnia of pharmaceutical sleep aids.

Digestive health and antispasmodic effects

Chamomile is one of the most used herbal remedies for GI complaints — functional dyspepsia, colic, gastritis, and IBS symptoms. Alpha-bisabolol reduces gastric inflammation, while the antispasmodic flavonoids relax intestinal smooth muscle to reduce cramping, bloating, and bowel irregularity.

Anti-inflammatory activity

Chamomile's chamazulene (formed during steam distillation) and alpha-bisabolol inhibit COX-2 and 5-LOX pathways, reducing prostaglandin and leukotriene production. Clinical studies confirm topical and oral chamomile reduces inflammatory markers — supporting use for mild inflammatory conditions.

Blood sugar regulation

A 8-week RCT showed chamomile tea (3 cups/day) significantly reduced fasting blood glucose, HbA1c, insulin, and HOMA-IR in type 2 diabetic patients vs. water control. Alpha-glucosidase inhibition and antioxidant protection of beta cells are proposed mechanisms.

1

Apigenin GABA-A receptor partial agonism

Apigenin — chamomile's primary flavonoid — binds the benzodiazepine site on GABA-A receptors as a partial agonist, enhancing inhibitory GABA neurotransmission and producing sedative-anxiolytic effects. Unlike benzodiazepines, apigenin's partial agonism produces milder effects without tolerance development or dependency risk.

2

Alpha-bisabolol anti-inflammatory and GI protective activity

Alpha-bisabolol inhibits NF-κB activation, reduces COX-2 expression, and protects gastric mucosa from irritant-induced damage. This anti-inflammatory and gastroprotective mechanism explains chamomile's efficacy for both systemic inflammation and GI-specific complaints.

3

Adenosine receptor modulation for sleep

Apigenin also binds central benzodiazepine receptors and modulates adenosine A1 receptors — contributing to sedative and sleep-promoting effects through both GABAergic and adenosinergic pathways simultaneously. This dual mechanism produces more natural sleep induction than single-pathway sleep aids.

1
Chamomile Extract for Generalized Anxiety Disorder — RCT
PubMed

Randomized, double-blind, placebo-controlled trial of chamomile extract (1,500 mg/day) vs. placebo in 179 adults with DSM-defined GAD for 8 weeks, with 26-week relapse prevention extension.

179 adults with GAD. 8-week treatment + 26-week relapse prevention.

Chamomile significantly reduced HAM-A scores vs. placebo. Sustained use reduced relapse rate by 56% vs. placebo withdrawal. Long-term chamomile use safe and effective for GAD maintenance. First robust RCT establishing chamomile for anxiety.

2
Chamomile Tea and Glycemic Control in T2DM — RCT
PubMed

Randomized controlled trial of chamomile tea (3 cups/day) vs. water in 64 type 2 diabetic patients for 8 weeks.

64 T2DM patients. 8-week intervention.

Chamomile tea significantly reduced fasting blood glucose, HbA1c, insulin, HOMA-IR, and antioxidant markers vs. water control. Supports chamomile as a safe daily beverage adjunct for blood sugar management.

Common Potential side effects

Allergic reactions in individuals sensitive to Asteraceae family (ragweed, chrysanthemums, daisies) — perform patch test or start low
Drowsiness with high doses — do not drive or operate machinery when first using
Rare anaphylaxis in highly sensitive Asteraceae-allergic individuals

Important Drug interactions

CNS depressants (benzodiazepines, alcohol, opioids) — additive sedative effects via GABA-A mechanism; use cautiously
Warfarin — chamomile contains coumarin derivatives; potential additive anticoagulant effect; monitor INR
Antidiabetic medications — additive glucose-lowering; monitor blood sugar
CYP1A2 substrates — apigenin inhibits CYP1A2; potential interaction with caffeine, theophylline, clozapine