Limited evidenceSleep & relaxation

American Skullcap

A traditional North American nervine herb (Scutellaria lateriflora) used for anxiety and restlessness. Only two small human trials exist, both in healthy volunteers rather than in people with an anxiety or sleep disorder.

Evidence last reviewed: August 2026

What the science says

Mood in healthy volunteers Limited evidence
A randomised, double-blind, placebo-controlled crossover study in 43 healthy volunteers reported improvements in some mood ratings after two weeks of skullcap without a loss of energy or cognition. The sample was small, the participants were not anxious at baseline, and the finding has not been replicated.
Acute anxiety reduction Limited evidence
An earlier small placebo-controlled trial in healthy volunteers found reductions in several anxiety measures after single doses of skullcap. Both human studies come from the same narrow literature and neither tested clinical anxiety disorders.
Use for sleep Limited evidence
No controlled trial has measured sleep latency or sleep quality with American skullcap. Its reputation as a sleep herb comes from traditional use and from its flavonoid affinity for benzodiazepine binding sites in laboratory assays, not from clinical outcomes.

Dosage & safety

Studied doseThe mood study used 1050 mg per day of dried aerial parts in divided doses; earlier work used 100–350 mg of extract. Typical commercial doses are 350–1000 mg of dried herb, or 2–4 mL of tincture, taken up to three times daily.

SafetyShort-term use appears well tolerated in the small trials available. Rare case reports link skullcap products to liver injury, though many involved adulteration with germander (Teucrium), a genuinely hepatotoxic plant — buy from suppliers who verify species identity. Avoid combining with sedatives or alcohol; avoid in pregnancy, breastfeeding and existing liver disease.

Scientific references

American Skullcap (Scutellaria lateriflora): a randomised, double-blind placebo-controlled crossover study of its effects on mood in healthy volunteers
Brock C, Whitehouse J, Tewfik I — Phytother Res, 2014
An investigation into the efficacy of Scutellaria lateriflora in healthy volunteers
Wolfson P, Hoffmann DL — Altern Ther Health Med, 2003

Where to buy

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