Seligiline transdermal system in depression

Seligiline, a monoamine oxidase inhibitor, has been previously approved by the US FDA for adjunctive treatment of Parkinson's disease. At present, it has been found to be effective in a transdermal system when administered daily in the treatment of major depressive disorder. The minimum dosage of 6 mg/24 h was effective in two trials; this dosage did not require any dietary precautions. Higher doses of 9 mg/24 h and 12 mg/24 h may also not require restrictions, however, current data is insufficient. Furthermore, a randomized 52-week prevention study found significant benefits for continuance of this treatment. There are several types of safety data available. First, there have been no reports of hypertensive crisis in any patient receiving selegiline via this transdermal system at any of the three doses. Tyramine challenge studies have found a comfortable cushion of safety at selegiline doses of 6 mg/24 h. Other side effects include a slightly higher rate of orthostatic hypotension, insomnia and, most frequently, application site reactions. There are no significant effects on weight or sexual side effects. In terms of drug interactions, carbamazepine was found to significantly increase seligiline levels (however, carbamazepine should be contraindicated). Direct sympathomimetics may be safe, but indirect ones are thought to put the patient at risk. Finally, due to risk of serotonin syndrome, other medications contraindicated include: selective serotonin re-uptake inhibitors, serotonin-noradrenaline re-uptake inhibitors and multiple analgesics - in particular meperidine. To prevent toxic drug interactions at initiation of seligiline transdermal system therapy, all mediactions that are at risk should be completely stopped a minimum of 4-5 times their respective half-lifes for full elimination. This is generally a time period of 1 week. Upon stopping treatment with selegiline, 2 weeks should pass prior to beginning any medication at risk for drug interactions.