Selegiline: What It Is, How It Works, and What You Need to Know

When you hear selegiline, a selective monoamine oxidase-B inhibitor used to treat Parkinson’s disease and sometimes depression. Also known as L-deprenyl, it works by blocking the enzyme that breaks down dopamine in the brain—helping keep more of this mood and movement chemical active. Unlike older MAO inhibitors, selegiline doesn’t mess with serotonin or norepinephrine as much, which means fewer dietary restrictions and lower risk of dangerous interactions—unless you’re taking other antidepressants or opioids.

It’s not just for Parkinson’s. People with early-stage Parkinson’s often take selegiline to slow symptom progression and reduce the need for higher doses of levodopa later. For depression, especially treatment-resistant cases, it’s sometimes used off-label in patch form (Emsam), which avoids the gut and liver, making it safer than pills. The patch delivers the drug through the skin, so you don’t have to worry about eating aged cheese or drinking red wine—something older MAO inhibitors forced you to avoid.

But it’s not harmless. Common side effects include dizziness, dry mouth, trouble sleeping, and nausea. In rare cases, it can cause hallucinations or sudden drops in blood pressure, especially if combined with certain pain meds or SSRIs. That’s why it’s critical to tell your doctor about every supplement, OTC drug, or herb you’re taking—even if you think it’s harmless. Selegiline can also interact with stimulants like ADHD meds or even some cold medicines containing dextromethorphan.

What makes selegiline stand out is how targeted it is. It doesn’t flood your system. It just helps your brain hold onto more of what it already makes. That’s why it’s often paired with levodopa in Parkinson’s care—it doesn’t replace the main drug, it makes it last longer. And because it’s been around for decades, there’s a lot of real-world data on who benefits most: typically, people in the early stages of Parkinson’s, or those who can’t tolerate other treatments.

There’s also growing interest in its potential neuroprotective effects. Some studies suggest selegiline might slow nerve cell death in Parkinson’s, though it’s not a cure. It’s one of the few drugs that might actually delay worsening—not just mask symptoms. That’s why doctors still prescribe it, even with newer options available.

It’s not a magic pill. But for many, it’s a quiet, steady helper. If you’re on it, tracking your doses and symptoms matters. A simple medication log can help you spot patterns—like whether your tremors improve after lunch or if you’re getting more jittery after skipping a meal. That’s the kind of detail that turns a generic prescription into a personalized treatment plan.

Below, you’ll find real stories and science-backed advice on using selegiline safely, avoiding dangerous combos, managing side effects, and understanding how it fits into the bigger picture of brain health and chronic disease care.