Postural hypotension, with monoamine oxidase inhibitors

From the existing literature, St. John s wort appears to be a safe and effective alternative in the treatment of depression. Tricyclic antidepressants and monoamine oxidase inhibitors can produce serious cardiac side effects, such as tachycardia and postural hypotension, and many unwanted anticholinergic side effects, including dry mouth and constipation. St. John s wort has proved to be free of any cardiac, as well as anticholinergic, side effects normally seen with antidepressant medications. Based upon limited studies, St. John s wort appears to be an acceptable alternative to traditional antidepressant therapy. 

Postural hypotension is common and often asymptomatic, and tends to diminish with continuing treatment. Hypertension may also occur, especially in the presence of nonselective monoamine oxidase inhibitors or sympathomimetics or when massive doses of levodopa are being taken. 

The monoamine oxidase inhibitors are associated with a number of undesirable side effects including weight gain, postural hypotension, sexual dysfunction, and insomnia. The most serious side effect is the risk of tyramine-re-lated hypertensive crisis, often referred to as the "cheese effect," which can be fatal. To avoid this situation patients taking MAOIs must limit their tyramine intake, and the restrictive diet required to accomplish this leads to low patient compliance. A similar interaction occurs when switching patients from MAOI to SSRI therapy, and a minimum 2-week washout period before commencement of SSRI therapy is essential to allow MAO levels to return to normal. The therapeutic effects of the TCAs derive from their inhibition of serotonin and norepinephrine uptake, al-... 

Selective serotonin reuptake inhibitors (SSRIs) are regarded as first-line treatment in social phobia. Fluvoxamine, paroxetine, and sertraline have been shown to be effective in double-blind placebo-controlled studies. - The irreversible monoamine oxidase inhibitor (MAOI) phenelzine shows robust results in terms of efficacy and has demonstrated (at least anecdotally), its efficacy in improving some of the cognitive aspects associated with SAD. However, phenelzine is usually less well tolerated than alternative treatments due to its associated dietary restrictions and adverse side-effect profile, including sedation and postural hypotension. Results with the reversible inhibitor of monoamine oxidase type A (RiMA) mociobemide are inconsistent. 

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