Herbal medicine and psychiatric disorders

The article in the March issue of BCMJ (“Self-report of use of traditional Chinese medicine by patients attending a cross-cultural psychiatry outpatient clinic,” 2007;49[2]:68-71) reported 20% of Chinese patients attending a cross-cultural psychiatry outpatient clinic in Vancouver had used traditional Chinese medicine (TCM). Many of those patients took the TCM products for somatic symptoms and not specifically for emotional symptoms.

Panax ginseng may cause manic-like symptoms when combined with monoamine oxidase inhibitors. [1]

St. John’s wort is self-medicated by Caucasians and individuals of various ethnocultural groups for depression. Clinical studies have demonstrated clinical efficiency for mild depression. [2] However, its use in moderate to severe depression is controversial.[3-6]

The production of hepatic cytochrome P450 3A4 enzyme, [7] and active efflux pump P-glycoprotein are increased by St. John’s wort. It affects the metabolism of 50% of all marketed medications and reduces their serum concentrations.

Many drugs metabolized by CYP 3A4 enzyme and reported to be affected by concurrent use of St. John’s wort include antidepressants (selective serotonin re-uptake inhibitor, tricyclic), HIV drugs, antihypertensives, anesthetics, warfarin, theophylline, digoxin, immunosuppressives, oral contraceptives, tamoxifen, sympathomietics, and others.

Acute onset of serotonin syndrome with hypertension, diaphoresis, agitation, dizziness, and weakness has been reported on two patients after 10-day use of St. John’s wort. The syndrome resolved following supportive care and discontinuation of St. John’s wort. [8]

In the article, the clinic psychiatrist advised the patients to discontinue the TCM. The authors cautioned the potential of toxic ingredients and potential interactions with Western psychotropic medications.

TCM and other herbal medicine can have adverse reaction and interaction with many different classes of Western medications. They should also be discontinued 2 weeks prior to elective surgeries because they may cause bleeding and have an effect on blood pressure and anesthetics. In addition, allergic reaction can occur,[9] and contaminant or adulterant may be present.[10]

—H.C. George Wong, MD
Vancouver

References

1. Shader RI, Greenblatt D. Bees, ginseng and MAOIs revisited. J Clin Psychopharmacol 1988;8:235. PubMed Citation
2. Linde K, Knupple L. Large-scale observational studies of hypericum extracts in patients with depressive disorders—A systematic review. Phytomedicine 2005;12:148-157.PubMed Abstract
3. Hypericum Depression Trial Study Group. Effect of Hypericum perforatum (St. John’s wort) in major depressive disorder: A randomized controlled trial. JAMA 2002;287:1807-1814. PubMed Abstract Full Text
4. Kasper S, Anghelescu IG, Szegedi A, et al. Superior efficiency of St John’s wort extract WS 5570 compared to placebo in patients with major depression: A randomized, double-blind, placebo-controlled, multi-center trial. BMC Med 2006;4:14. PubMed Abstract Full Text
5. Szegedi A., Kohnen R, Dienel A, et al. Acute treatment of moderate to severe depression with hypericum extract WS 5570 (St. John’s wort): Randomized controlled double-blind non-inferiority trial versus paroxetine. BMJ 2005;330:503. PubMed Abstract Full Text
6. Linde K, Mulrow CD, Berner M, et al. St. John’s wort for depression. Cochrane Database Syst Rev 2005;(2);CD 000448. PubMed Abstract Full Text
7. Markowitz JS, Donovan JL, DeVane CL, et al. Effect of St. John’s wort on drug metabolism by induction of cytochrome P450 3A4 enzyme. JAMA 2003;290:1500-1504. PubMed Abstract Full Text
8. Parker V, Wong AH, Boon HS, et al. Adverse reactions to St. John’s wort. Can J Psychiatry 2001;46:77-79. PubMed Abstract
9. Wong HCG. Allergic contact dermatitis from topical Chinese herbal medicine and generalized urticaria and angioedema from dietary supplementation: A case report. BCMJ 2002;44:184-187. Full Text
10. Wong HCG. Mercury and Chinese herbal medicine. BCMJ 2004;46:442. Full Text