Generally speaking, herbs should be combined cautiously with antidepressants and patients should be monitored carefully after starting combination therapy. There are few studies on whether herbs and antidepressant drugs work together well or might cause adverse effects. As cited above, St. John’s wort has been considered a potential threat in combination with antidepressant drugs, though very little evidence of difficulties has been documented. St. John’s wort should be used with caution with all types of antidepressant drugs but is not absolutely contraindicated in all cases. Table Antidepressant Drug-Herb Interactions reviews potential interactions of antidepressant drugs and herbs.
Table Antidepressant Drug-Herb Interactions
|Herb||Antidepressant Drug(s)||Nature of Interaction|
|Hypericum perforatum (St. John’s wort)||SSRIs, MAOs, tricyclic antidepressants||Unknown, potentially unsafe, do not combine without careful and close professional monitoring.|
|Ginkgo biloba||SSRIs, MAOs, tricyclic antidepressants||Preliminary study shows reduction in sexual side effects.|
|Potentiated benefits in one clinical trial.|
|Desipramine||No negative or positive interaction in clinical trials.|
|Bitters||SSRIs, MAOs, tricyclic antidepressants||No known or anticipated interaction.|
|EFAs||SSRIs, MAOs, tricyclic antidepressants||No known or anticipated interaction.|
|Nervines||SSRIs, MAOs, tricyclic antidepressants||Anticipated beneficial interaction, no reports of adverse interactions.|
|Stimulants||SSRIs, MAOs, tricyclic antidepressants||Avoid combination, theoretical anticipation of potential adverse interactions.|
|Stimulating immunomodulators||SSRIs, MAOs, tricyclic antidepressants||No known or anticipated interactions.|
|Peganum harmala (Syrian rue)||SSRIs, MAOs, tricyclic antidepressants||Combine with great caution (potential synergism due to similar mechanisms of action).
Theoretical potential for adverse interactions.
|Banisteriopsis caapi (ayahuasca)||MAOIs||Combine with great caution (potential synergism due to similar mechanisms of action).|
|Tricyclics, SSRIs||Theoretical potential for adverse interactions.|
|Volatile oils||SSRIs, MAOs, tricyclic antidepressants||Unknown.|
|Papaver somniferum (opium)||SSRIs, MAOs, tricyclic antidepressants||Unknown (serious potential for adverse interaction).|
|Ignatia amara and Strychnos nux-vomica||SSRIs, MAOs, tricyclic antidepressants||Unknown (serious potential for adverse interactions).|
Ginkgo has been successfully combined with antidepressants in one study. The goal of this uncontrolled study was to offset the very common incidence of reduced libido caused by SSRIs, tricyclic antidepressants, and MAO-inhibitor drugs. Ginkgo standardized extract at a dose of 60-120 mg two times per day was effective at preventing reduction of libido in 84% of people in the study. Women responded better than men. A further controlled clinical trial is warranted, though reducing side effects of antidepressant drugs should not be used as an excuse to avoid locating and treating the cause of depression.
Yohimbine is an alkaloid derived from the African plant Pausinystalia yohimbe (yohimbe) bark. It antagonizes alpha-2 adrenergic receptors. This is important in depression because alpha-2 receptors tend to exert a regulatory role that inhibits release of norepinephrine and possibly other catecholamines. It is believed that tricyclic antidepressants‘ effects are delayed at least in part due to up regulation of alpha-2 adrenergic receptors to compensate for the increased level of catecholamines induced by these nonselective catecholamine reuptake-inhibiting drugs. One study has shown that yohimbine (5-30mg three times per day) can enhance the antidepressant activity of the drug fluvoxamine (Luvox), whereas another study did not find yohimbine alone or combined with desipramine (Norpramin) effective in people with severe, refractory depression. Thus, there is a potential role for use of standardized extracts of yohimbe providing 5-10 mg three times per day of yohimbine alkaloid to augment antidepressant drugs in severe situations, but this is not an herb that should be dispensed in most cases. Yohimbe is absolutely contraindicated in people with panic disorder or posttraumatic stress disorder, both of which can be worsened by this herb. Above 10 mg three times per day of yohimbine, hypertension, agitation, and other adverse effects become much more common and disturbing, and such high doses are generally best avoided.