Uses

Used as an adjunct to levodopa/carbidopa therapy in Parkinson's disease to reduce end-of-dose motor fluctuations. Selegiline selectively inhibits MAO-B, reducing dopamine breakdown in the striatum.

Do not use if

Contraindicated with meperidine, tramadol, methadone, and other opioids due to risk of serotonin syndrome. Avoid concurrent use with other MAO inhibitors, SSRIs, SNRIs, and TCAs.

Side effects

Common side effects include nausea, dizziness, dry mouth, insomnia, and orthostatic hypotension, particularly when used with levodopa. May enhance dyskinesia associated with levodopa therapy.

Warnings

At doses above 10 mg/day, selectivity for MAO-B is lost and dietary tyramine restrictions become necessary. Serotonin syndrome risk is significant with concomitant serotonergic agents. Monitor for impulse control disorders associated with dopaminergic therapy.

How it works

Selegiline irreversibly inhibits monoamine oxidase type B (MAO-B), the enzyme primarily responsible for dopamine catabolism in the brain. This leads to increased synaptic dopamine levels, improving motor control in Parkinson's disease without the tyramine-induced hypertensive crisis risk seen with non-selective MAO inhibitors at therapeutic doses.

Storage

Store at controlled room temperature (15°C–30°C). Protect from light and moisture.