Herbal medicines

What are herbal medicines? 

Herbal treatments can include traditional Chinese medicines, as well as more common herbal medicines such as gingko biloba or folate. Herbal treatments have been suggested as an adjunctive therapy, which is a supplementary treatment administered in conjunction with a patient’s ongoing medications in an attempt to treat symptoms or improve functions that are not addressed by these medications alone.

What is the evidence for adjunctive herbal medicines?

High quality evidence shows adjunctive ginkgo biloba can improve symptoms, particularly when combined with chlorpromazine or haloperidol. Moderate quality evidence suggests adjunctive ginkgo may specifically be effective for the treatment of negative symptoms. Moderate to high quality evidence shows adjunctive folic acid can also improve negative symptoms, with fewer adverse effects than with adjunctive placebo.

Moderate to low quality evidence suggests adjunctive traditional Chinese medicines wendon decoction, hirudo seu whitmania, rhizome rheum palmatum, and xingshen may provide greater improvement in symptoms and better retention in treatment than antipsychotics alone. There may also be fewer side effects. Adjunctive suoquan wan may be more effective than the antimuscarinic, doxepin, for reducing clozapine-induced hypersalivation, and may result in less constipation.

Moderate to low quality evidence suggests adjunctive Vitamin B may provide a medium-sized improvement in overall symptoms compared with adjunctive placebo. No  benefit of Vitamin E was found for mental health symptoms or tardive dyskinesia.

March 2019

Last updated at: 11:55 pm, 20th March 2019
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