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 doesn’t just mask symptoms—it helps your brain hold onto dopamine longer, which is why it’s often paired with levodopa in Parkinson’s treatment. Unlike older MAO inhibitors that caused serious dietary restrictions, selegiline is more targeted. It mostly affects the brain, not the gut, which means you can eat most foods without worrying about dangerous spikes in blood pressure.

It’s not just for tremors. Studies show selegiline can help with low mood in people with Parkinson’s, and in some cases, it’s used off-label for treatment-resistant depression. It works differently than SSRIs—it doesn’t flood your system with serotonin. Instead, it stops the enzyme that breaks down dopamine and norepinephrine, letting those mood-boosting chemicals stick around longer. That’s why some people notice better energy, focus, and motivation, even before their motor symptoms improve.

But it’s not magic. Selegiline won’t fix everything. It’s most effective when used early in Parkinson’s, often as a first-line add-on. If you’re on other meds—like antidepressants, painkillers, or even some cold medicines—you need to be careful. Mixing it with SSRIs or tramadol can trigger serotonin syndrome, a rare but serious reaction. Your doctor will check your full list of meds before starting you on it.

Side effects aren’t usually scary—insomnia, dizziness, or dry mouth are common—but they’re real. Taking it too late in the day can keep you up all night. And if you’re over 65, your doctor might lower the dose. It’s not a drug you take lightly, but when it fits, it can make a noticeable difference in daily life.

People who use selegiline often compare it to other Parkinson’s options like rasagiline or entacapone. Each has pros and cons. Selegiline’s patch form (Emsam) is an option for depression without the pill schedule. The oral form is cheaper and widely available, but the patch avoids some stomach issues. What works for one person might not work for another—and that’s why knowing how it fits into your bigger picture matters.

Below, you’ll find real comparisons and deep dives on how selegiline stacks up against other treatments, what side effects to watch for, and how it interacts with other drugs you might be taking. Whether you’re managing Parkinson’s, exploring depression options, or just trying to understand why your doctor suggested this pill, you’ll find clear, no-fluff answers here.