American Skullcap
Also called skullcap, scullcap, Scutellaria lateriflora, blue skullcap, mad-dog skullcap.
Best grade D across 2 graded outcomes Botanical Last checked
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The short answer
From 6 sourcesAmerican skullcap (Scutellaria lateriflora) is a North American herb used for anxiety, stress and sleep. In 43 healthy adults, it did not lower anxiety scores vs placebo, though mood improved from baseline. An extract-based supplement improved sleep scores in 66 adults with insomnia. LiverTox links skullcap to rare liver injury, sometimes from adulterated products.
Quick pick
From a partner brand · paid link
Eclectic Herb Skullcap, 350 mg, 50 veg caps
from HerbsPro
Label: Each 350 mg capsule holds freeze-dried organic Scutellaria lateriflora flower and leaf.
Best for trying one bottle: $17.50 one-time (checked Oct 15, 2026).
Every graded outcome on this page
2 rows · line = participantsKey facts
- What it is
- Scutellaria lateriflora, a Native American plant used in teas and capsules; Chinese skullcap is a different species1
- Anxiety (43 adults)
- No difference from placebo on the Beck Anxiety Inventory (p = 0.191)2
- Mood
- Total mood disturbance fell from baseline on skullcap (p < 0.001) but not on placebo (p = 0.072)2
- Sleep (66 adults with insomnia)
- PSQI and sleep onset, efficiency and total sleep time improved vs placebo with a 400 mg a day extract-based supplement3
- Liver
- LiverTox rates skullcap a very likely but rare cause of clinically apparent liver injury (likelihood score B)1
What it is
American skullcap is Scutellaria lateriflora, a North American herb used in teas and capsules; it is a different plant from Chinese (Baikal) skullcap.
Forms, side by side
2 forms named in our sources. The rest show what our data holds, and say plainly where it holds nothing yet.
American Skullcap forms compared
2 forms| 2 forms | Dried skullcap leaf and flower (capsules or tea) | Characterized Scutellaria lateriflora extract |
|---|---|---|
| Absorption in people | Not measured; the trial tracked anxiety and mood scores.2 | Not measured.3 |
| GI tolerance | The mood trial reported improved mood without lower energy or cognition; LiverTox links skullcap to rare liver injury.21 | No participant reported adverse effects over 56 days.3 |
| Studied for | Anxiety and mood (350 mg three times a day) | Sleep in primary insomnia (400 mg a day) |
- Dried skullcap leaf and flower (capsules or tea)
- Characterized Scutellaria lateriflora extract
What the human research says
Human trials only, one row per outcome. The form line shows what each trial actually tested. Grades follow our evidence-grading policy.
Trial map
2 graded outcomes, largest study first2 graded outcomes: 1 improved, 1 mixed. The largest, a 2025 crossover trial of 66 people on sleep quality in mild to moderate primary insomnia, found an improvement.
1Sleep quality in mild to moderate primary insomnia
Improved · Grade D · Crossover RCT, 66 people, 2025
Adults aged 18 to 70 with mild to moderate primary insomnia
Dose, result and source| Outcome | Found | People | Study | Who was studied |
|---|---|---|---|---|
| Sleep quality in mild to moderate primary insomnia | Improved | 66 | Grade D · Crossover RCT, 2025 | Adults aged 18 to 70 with mild to moderate primary insomnia |
| Anxiety and mood in healthy adults | Mixed | 43 | Grade D · Crossover RCT, 2014 | Healthy volunteers, 81% mildly anxious or less at baseline |
Every graded row
2 rowsDGrade DSleep quality in mild to moderate primary insomniaSleep qualityBetter sleep scoresCrossover RCT
n 66 · 2025
Improved PSQI (primary outcome) and sleep onset latency, sleep efficiency and total sleep time improved vs placebo; no participant reported adverse effects.
- Design
- Crossover RCT, n = 66, 2025
- Population
- Adults aged 18 to 70 with mild to moderate primary insomnia
- Form
- Characterized Scutellaria lateriflora extract-based food supplement
- Dose
- 400 mg a day
- Duration
- 56 days per treatment, 28-day washout
- Source
- Reference 3 · PubMed 40362800 (opens PubMed)
DGrade DAnxiety and mood in healthy adultsAnxiety and moodNo anxiety effect; mood up vs baselineCrossover RCT
n 43 · 2014
Mixed Anxiety (Beck Anxiety Inventory) did not differ from placebo (p = 0.191); total mood disturbance fell from baseline with skullcap (p < 0.001) but not placebo (p = 0.072).
- Design
- Crossover RCT, n = 43, 2014
- Population
- Healthy volunteers, 81% mildly anxious or less at baseline
- Form
- Scutellaria lateriflora
- Dose
- 350 mg three times a day
- Duration
- 2 weeks per treatment
- Source
- Reference 2 · PubMed 23878109 (opens PubMed)
Human studies not graded here
2 notesThese studies involved people but cannot be graded as an outcome on this page.
- Anxiety in healthy volunteers (2003)
- An early double-blind, placebo-controlled study in healthy volunteers reported noteworthy calming effects, but its abstract gives no participant count, dose or effect size, so it is not graded. The later 43-person trial found no difference from placebo on anxiety scores.52
- Gum inflammation (combination chewing gum)
- In 60 adults with gingivitis, two chewing gums a day containing American skullcap and Cistus × incanus extracts for 3 months lowered gum-bleeding, pain and severity scores, while the placebo group did not change. The gum combined two herbs, so the effect cannot be credited to skullcap alone.6
What the numbers add up to
Each point is worked out from the data and the sources numbered on this page, with the arithmetic shown under it. It adds no new data and is not medical advice.
Mood moved, anxiety did not
In the 43-person crossover, anxiety scores did not separate from placebo; mood improved only versus baseline, and a carryover effect blurred the comparison.2
Sleep evidence is one product
The 66-person insomnia trial tested a single extract-based product, and its abstract reports no effect sizes.3
Studied doses
Doses used in research, shown against the official limits. They describe the studies, not a recommendation for you.
Studied doses in research, not advice. These are amounts used in research, not personal advice. Your clinician or pharmacist can say what fits you.
Doses studied in human trials
Interactions and safety
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
Interactions
0 agentsNone found in our sources.
Check with what you take
Kept on this device onlyAdd what you take. We list every interaction our evidence profiles cite between American Skullcap and your picks, and between your picks.
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Add a supplement or medicine you take to check it against American Skullcap.
Starting from one medicine? The interaction checker rates how serious each pair is, on a curated list of 19 entries for 11 medicines. This cabinet has no severity rating: it lists every interaction row our supplement pages cite.
Who should be careful
4 groups- Liver disease or liver symptoms
- LiverTox links skullcap to rare liver injury, with symptoms 1 to 12 weeks after starting; most cases resolved quickly after stopping, but at least one acute liver failure has been reported.1
- Adulterated or mixed products
- LiverTox notes most cases involved several herbs taken together, and some suspected cases were traced to adulteration with germander or mislabeling.1
- Medicines and surgery
- NCCIH advises that supplements may interact with medications or pose risks before surgery, and to tell your health care providers about everything you use.4
- Pregnancy, breastfeeding and children
- No skullcap trial enrolled pregnant or breastfeeding women or children, and we found no LactMed (breastfeeding) entry for skullcap, so there are no reliable safety data. NCCIH notes that many dietary supplements have not been tested in pregnant women, nursing mothers or children.423
How to read the label
What to check on the Supplement Facts panel.
How to read the label
1 checksCheck the species
American skullcap is Scutellaria lateriflora; Chinese skullcap (Scutellaria baicalensis) is a different plant that LiverTox also ties to liver injury.1
Where to buy American Skullcap
Products from brands we partner with that contain American Skullcap. Check the amount per serving against the doses studied above, and the label for other ingredients.
American Skullcap products from partner brands
1 product Paid links · we earn a commission- Quick pickHerbsProEclectic Herb Skullcap, 350 mg, 50 veg caps
Each 350 mg capsule holds freeze-dried organic Scutellaria lateriflora flower and leaf; the 2014 mood trial gave 350 mg three times a day
$17.50one-timeChecked Oct 15, 2026
Frequently asked questions
Short answers to common questions; the numbers link to the sources below.
Common questions
8 answersDoes American skullcap help anxiety?
In 43 healthy adults, 350 mg three times a day did not lower anxiety scores vs placebo (p = 0.191), though total mood disturbance fell from baseline. Most participants were not very anxious to begin with.2
Does skullcap help with sleep?
In 66 adults with mild to moderate insomnia, a 400 mg a day extract-based supplement improved PSQI scores and sleep onset, efficiency and total sleep time vs placebo over 56 days.3
Is skullcap bad for the liver?
LiverTox rates it a very likely but rare cause of liver injury. Most cases involved several herbs or adulteration with germander, and most resolved after stopping, but at least one acute liver failure has been reported.1
What are the side effects of American skullcap?
Does American skullcap interact with medications?
Is American skullcap safe during pregnancy or breastfeeding?
There are no reliable data: no trial enrolled pregnant or breastfeeding women, and there is no LactMed entry for skullcap.4
What is the difference between American and Chinese skullcap?
American skullcap is Scutellaria lateriflora, a North American plant; Chinese skullcap is Scutellaria baicalensis, a different species also linked to liver injury.1
Sources
6 sources: trial abstracts, NIH fact sheets and reference databases. Numbers in the text link here.
Sources cited on this page
6 sources- 1Skullcap. LiverTox: Clinical and Research Information on Drug-Induced Liver InjuryDatabase National Institute of Diabetes and Digestive and Kidney Diseases, via NCBI Bookshelf, 2020 · ncbi.nlm.nih.gov
- 2American Skullcap (Scutellaria lateriflora): a randomised, double-blind placebo-controlled crossover study of its effects on mood in healthy volunteers.Crossover RCT Phytother Res, 2014 · PMID 23878109
- 3Efficacy and Tolerability of a Chemically Characterized Scutellaria lateriflora L. Extract-Based Food Supplement for Sleep Management: A Single-Center, Controlled, Randomized, Crossover, Double-Blind Clinical Trial.Crossover RCT Nutrients, 2025 · PMID 40362800
- 4Using Dietary Supplements WiselyFact sheet National Center for Complementary and Integrative Health (NCCIH), 2019 · nccih.nih.gov
- 5An investigation into the efficacy of Scutellaria lateriflora in healthy volunteers.RCT Altern Ther Health Med, 2003 · PMID 12652886
- 6Efficacy and Tolerability of a Scutellaria lateriflora L. and Cistus × incanus L.-Based Chewing Gum on the Symptoms of Gingivitis: A Monocentric, Randomized, Double-Blind, Placebo-Controlled Clinical Trial.RCT Nutrients, 2024 · PMID 38542772
What changed
Every dated change to this page: what changed, who made it and why.
Change log
2 entries| Date | Change | Who and why |
|---|---|---|
| all | PubMed search (to October 2026) found no newer trial of American skullcap alone; added an ungraded research note on the 2003 volunteer study and a 2024 combination chewing-gum trial for gingivitis, a cited pregnancy and breastfeeding note, three FAQs (side effects, pregnancy, interactions) and page questions. Interactions checked: LiverTox, NCCIH and PubMed document no specific drug interactions and there is no LactMed entry, so the interaction list stays empty. Added sleep and stress goal-hub links. | Writer: Kymata Health EditorialTrigger: A–Z audit against docs/supplements/AUDIT-STANDARD.md |
| all | Initial editorial evidence review. Every PMID checked against NCBI E-utilities esummary (title, year, journal; none retracted) and each cited abstract read; numbers taken from the abstracts. Funding and conflicts: one CEINGE-Biotecnologie Avanzate employee (2025 insomnia); the 2014 abstract names no funder (PubMed lists non-US government support). Null anxiety result shown (p = 0.191). Safety from LiverTox (NBK548757, updated 2020-03-28) plus NCCIH general guidance. Where to buy: Eclectic Herb Skullcap 350 mg (checked 2026-10-15). | Writer: Kymata Health EditorialTrigger: new page |
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