Skullcap

Skullcap (Scutellaria lateriflora) has been used for over two hundred years as a mild relaxant that affects the nervous and musculoskeletal systems. It has long been hailed as an effective therapy for anxiety, nervous tension, hysteria, and convulsions and is currently also used for treating symptoms associated with premenstrual syndrome (PMS), stress-related headaches, and insomnia. Once considered an herbal remedy for rabies, thus earning the name "mad dog weed," skullcap is no longer recognized as a treatment for this disease.

Plant Description

Scutellaria lateriflora is the North American species of skullcap, now also widely cultivated in Europe, that is used in herbal preparations. The plant derives its name from the caplike appearance of the calyx, the outer whorl of small blue flowers. Skullcap is a slender, heavily branched plant that grows to a height of two to four feet and blooms each July.

Parts Used

The herb from a three- to four-year-old skullcap plant harvested in June is used for medicinal purposes.

Medicinal Uses/Indications

Skullcap is used to treat the following conditions and symptoms.

• Anxiety
• Nervous tension, anxiety, muscle spasm
• PMS-related symptoms
• Stress-related headaches
• Insomnia
• Restless legs syndrome
• Mild Tourette's syndrome

Available Forms

Skullcap is available as a powder or liquid extract.

How to Take It

The following are recommended doses for skullcap.

• Dried herb: 1 to 2 g or by infusion three times per day
• Fluid extract (1:1 in 25% alcohol): 2 to 4 ml three times per day
• Tincture (1:5 in 45% alcohol): 2 to 5 ml three times per day

Precautions

There is mixed opinion as to the safety of skullcap because it has in the past been adulterated with Teucrium species, a group of plants known to cause liver problems. You should consult your health care provider before using it, and make sure you obtain it from a reliable source. Overdosage of skullcap tincture produces symptoms of giddiness, stupor, mental confusion, seizure, twitching, irregular heartbeat, and epileptic-related symptoms. Skullcap should not be used during pregnancy and breast-feeding. Other experts caution against using skullcap under any circumstances because of the possibility of adulteration.

Possible Interactions

There are no known reports of harmful drug interactions with this herb. However, caution is advised when taking skullcap with medications that have sedative effects because skullcap may increase the effects of these substances. Examples of medications with sedative properties include most antihistamines and therapies for anxiety and insomnia.

Supporting Research

Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, Ore: Eclectic Medical; 1998:163.

Grieve M. A Modern Herbal. Vol. II. New York: Dover; 1971: 724-725.

Gruenwald J, Brendler T, Christof J. PDR for Herbal Medicines. Montvale, NJ: Medical Economics Company; 1998: 1128-1129.

Newall C, Anderson L, Phillipson J. Herbal Medicines: A Guide for Health-care Professionals. London: Pharmaceutical Press; 1996: 239-240.

Peigen X, Keji C. Recent advances in clinical studies of Chinese medicinal herbs. I. Drugs affecting the cardiovascular system. Phytotherapy Res. 1987; 1: 53-57.

Kimura Y, et al. Studies on Scutellariae radix. IV. Effects on lipid peroxidation in rat liver. Chem Pharm Bull. 1981; 29: 2610-2617.

Kimura Y, et al. Studies on Scutellariae radix. VI. Effects of flavone compounds on lipid peroxidation in rat liver. Chem Pharm Bull. 1982; 30(5): 1792-1795.

Kimura Y, et al. Studies on Scutellariae radix. IX. New component inhibiting lipid peroxidation in rat liver. Planta Med. 1984; 50:290-295.

Kubo M, et al Scutellariae radix. X. Inhibitory effects of various flavonoids on histamine release from rat peritoneal mast cells in vitro. Chem Pharm Bull. 1984; 32: 5051-5054.

Kurnakov BA. Pharmacology of skullcap. Farmakol i Toksikol. 1957; 20: 79-80.

Larrey D, et al. Hepatitis after germander (Teucrium chamaedrys) administration: another instance of herbal medicine toxicity. Ann Coll Physicians. 1992; 117: 129-132.

Copyright © 2000 Integrative Medicine Communications

The publisher does not accept any responsibility for the accuracy of the information or the consequences arising from the application, use, or misuse of any of the information contained herein, including any injury and/or damage to any person or property as a matter of product liability, negligence, or otherwise. No warranty, expressed or implied, is made in regard to the contents of this material. No claims or endorsements are made for any drugs or compounds currently marketed or in investigative use. This material is not intended as a guide to self-medication. The reader is advised to discuss the information provided here with a doctor, pharmacist, nurse, or other authorized healthcare practitioner and to check product information (including package inserts) regarding dosage, precautions, warnings, interactions, and contraindications before administering any drug, herb, or supplement discussed herein.