Alternative Therapies: Part I. Depression, Diabetes, Obesity
Alternative Therapies: Part I. Depression, Diabetes, Obesity
VINCENT MORELL and ROGER J. ZOOROB
American Family Physician


Natural supplements are widely used in the United States and, while claims of their therapeutic effects abound, medical research does not always support their effectiveness. St. John's wort acts as a weak selective serotonin reuptake inhibitor with fewer side effects. S-Adenosylmethionine (SAMe) has enough of an antidepressant effect to warrant further research. More human studies are needed before garlic, bitter melon, soy and fenugreek supplements can be recommended for the management of diabetes, although chromium may be a promising treatment in some cases. Alpha lipoic acid is used in the treatment of diabetic neuropathy. The effects of ma huang/guarana combinations in obesity have not been well studied. These combinations may have potentially serious side effects but may also offer some benefit. The combination of hydroxycitric acid and garcinia has proved no more effective than placebo. (Am Fam Physician 2000;62:1051-60.)

Depression

The effectiveness and side effects of selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs) are well documented. Relatively new potential additions to the armamentarium against depression include St. John's wort and S-adenosylmethionine (SAMe).

St. John's wort (Hypericum perforatum) appears to act as a weak SSRI and may have an affinity for sigma receptors as well. Its clinical effectiveness may be attributable to a combination of mechanisms because each mechanism by itself is too weak to provide the overall effect.4,5

Studies have compared TCAs (i.e., imipramine [Tofranil], amitriptyline [Elavil]) with St. John's wort in cases of mild to moderate depression and found no statistical differences between groups as evaluated by the Hamilton Depression Scale. One-third fewer side effects were noted in the subjects taking St. John's wort, compared with the subjects taking amitriptyline.6

Initially, it was thought that this botanical supplement rarely, if ever, led to any drug interactions.7 However, recent evidence8,9 indicates interactions with digoxin, theophylline (decreased bioavailability), protease inhibitors (lowering the level of indinavir [Crixivan]), and drugs used to combat transplant rejection (increasing the metabolism of cyclosporine [Sandimmune]) via induction of cytochrome P450 enzymes. It also may cause seratonin syndrome if used with other antidepressants.

Results of 29 clinical trials10,11 have demonstrated that St. John's wort is more effective than placebo in the treatment of mild to moderate depression. As yet, there is insufficient evidence comparing the efficacy of St. John's wort with conventional, modern antidepressants. We could find no studies that used St. John's wort in combination with other modalities to treat severe depression or treatment-resistant depression, and it should not be used in these patients.

Copyright © 2000 by the American Academy of Family Physicians.