Scullcap

Scientific Name(s): Scutellaria lateriflora L.
Common Name(s): Helmetflower, Hoodwort, Mad-dog weed, Scullcap, Skullcap

Medically reviewed by Drugs.com. Last updated on Sep 13, 2021.

Clinical Overview

Use

Scullcap traditionally has been used as a sedative for nervousness and anxiety, although data are limited to support this use. Benefit for mood disturbance has also been demonstrated.

Dosing

Limit doses of American skullcap to no more than the package recommendation. Typical doses (see individual product information): Dried herb: 1 to 2 g 3 times/day; Tea: 240 mL 3 times/day (pour 250 mL of boiling water over 5 to 10 mL of the dried herb and steep for 10 to 15 minutes); Tincture: 2 to 4 mL 3 times/day. Mood disturbance: 350 mg capsules consisting of freeze-dried S. lateriflora whole aerial parts (not a standardized extract) given 3 times daily for 2 weeks.

Contraindications

Contraindications have not yet been identified.

Pregnancy/Lactation

Documented adverse effects in pregnancy. Avoid use. May inhibit pituitary and chorionic gonadotropins, as well as prolactin.

Interactions

None well documented, though it may exaggerate the effects of other drugs that cause drowsiness.

Adverse Reactions

If taken according to the manufacturer's directions, scullcap does not seem to exhibit any adverse effects. Minor and infrequent side effects have been reported from a small clinical trial including vivid dreams, feeling spaced out, and mild digestive disturbances.

Toxicology

An overdose of the tincture causes giddiness, stupor, confusion, twitching of the limbs, intermission of the pulse, and other symptoms similar to epilepsy.

Scientific Family

• Lamiaceae (mint)

Botany

Scullcap (S. lateriflora), a member of the mint family, is native to the United States where it grows in moist woods. Although it is widely distributed throughout large regions of North America, there are related species found as far away as China. There are over 300 species of Scutellaria worldwide. Common scullcap (Scutellaria lateriflora) is the best known of these species.

Scullcap is an erect perennial that grows to 1 m in height. Its bluish flowers bloom from July to September. Official compendia recognize only the dried overground portion of the plant as useful; however, some herbal texts list all parts as medicinal.1 The aerial parts of the plant are collected during the flowering period, typically August and September. It is important to note the difference between American skullcap (S. lateriflora) and S. baicalensis (otherwise known as Chinese skullcap), which is a related plant.2 The members of this diverse genus are not generally interchangeable.2 A number of species have been used medicinally, and the most common European variety is S. baicalensis, a native of East Asia (see Baical Skullcap monograph).

History

Scullcap appears to have been introduced into traditional American medicine toward the end of the 1700s, when it was called mad-dog skullcap because of its use as a treatment for rabies. It was later used as a tonic, particularly in proprietary remedies for "female weakness."3 The plant was reputed to be an herbal tranquilizer, particularly in combination with valerian, but has fallen into disuse.

Scullcap has traditionally been used to treat nervousness, irritability, and neuralgia, as well as for its sedative properties.

Chemistry

The various species of Scutellaria contain several flavonoid glycoside pigments. These include scutellarein, wogonin, is...