Skullcap can refer to 2 herbs: American skullcap (Scutellaria lateriflora) and Chinese skullcap (Scutellaria baicalensis). Both forms of skullcap are used to treat different conditions and are not interchangeable.
American skullcap is native to North America, but it is now widely cultivated in Europe and other areas of the world. It has been used for more than 200 years as a mild relaxant and as a therapy for anxiety, nervous tension, and convulsions. Studies show American skullcap has significant antioxidant effects, and may help protect against neurological disorders, such as Alzheimer's disease, Parkinson's disease, anxiety, and depression. There's even some evidence to suggest that American skullcap may inhibit food allergic response. Today, other herbs (such as valerian) are more commonly used, although American skullcap may be combined with other calming herbs in some preparations.
Most of the studies done on skullcap have examined Chinese skullcap. Native to China and parts of Russia, Chinese skullcap has been used in traditional Chinese medicine to treat allergies, infections, inflammation, cancer, and headaches. It may also have antifungal and antiviral effects. Animal studies suggest that Chinese skullcap may help reduce symptoms of diabetes and hypertension (high blood pressure), but scientists don't know if Chinese scullcap has the same effect in humans. In test tubes and animal studies, Chinese skullcap appears to have some cancer-fighting properties. More research is needed to determine any benefit.
Neither American skullcap nor Chinese skullcap is recommended for children.
Skullcap is available as an encapsulated dried herb, tea, fluid extract, and tincture. Speak to your physician to find the right form and dose for your needs.
Chinese skullcap is often combined with other herbs into a preparation; follow dosing recommendations on the label.
If you are being treated with any of the following medications, you should not use either American skullcap or Chinese skullcap without first talking to your health care provider.
Both American skullcap and Chinese skullcap can increase the effect of drugs that have a sedating effect, including:
- Anticonvulsants, such as phenytoin (Dilantin) and valproic acid (Depakote)
- Benzodiazepines, such as alprazolam (Xanax) and diazepam (Valium)
- Drugs to treat insomnia, such as zolpidem (Ambien), zaleplon (Sonata), eszopiclone (Lunesta), and ramelteon (Rozerem)
- Tricyclic antidepressants, such as amitriptyline (Elavil)
The same is true of herbs with a sedating effect, such as valerian, kava, and catnip.
Drugs for Diabetes
Chinese skullcap can lower blood sugar, and could strengthen the effects of drugs taken for diabetes, increasing the risk of hypoglycemia (low blood sugar).
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