Head-to-head comparisons of medication uses, side effects, warnings, and more.
Key takeaways
Selegiline (Zelapar) and amantadine (Symmetrel) are both used to treat symptoms of Parkinson's disease (PD), but they work in different ways and belong to different drug classes. Selegiline is a monoamine oxidase type B (MAO-B) inhibitor that helps prevent the breakdown of dopamine in the brain, thereby extending the effects of levodopa. It is typically used as an add-on treatment for those already taking carbidopa/levodopa. On the other hand, amantadine is an N-methyl-D-aspartate (NMDA) antagonist that raises dopamine levels by blocking NMDA receptors, which helps relieve movement symptoms like trembling and stiffness. Amantadine can be used alone or with other PD medications. Selegiline is available in tablets, capsules, and orally disintegrating tablets (ODTs), while amantadine is available in oral form and as a solution for those who have trouble swallowing pills. Both medications can cause nausea and dizziness, but selegiline can cause high blood pressure if taken with tyramine-rich foods, while amantadine can lead to mood changes and hallucinations. Additionally, selegiline must be taken with caution to avoid serotonin syndrome if combined with certain medications, whereas amantadine requires careful monitoring for withdrawal symptoms if stopped suddenly.
Selegiline
Amantadine
Selegiline
Amantadine
Summary of Zelapar vs. Symmetrel
Summary for MAO-B inhibitor
Prescription only
Selegiline helps relieve symptoms of Parkinson's disease in people who have "off" episodes as their carbidopa/levodopa medication starts to wear off. Selegiline is a type of monoamine oxidase inhibitor (MAOI), which is a drug class that has many drug interactions. Generic selegiline tablets and capsules are taken twice per day; the brand name for the pills, Eldepryl, is no longer available. Selegiline also comes as orally disintegrating tablets (ODTs) under the brand name Zelapar that are dissolved on the tongue once per day. Side effects include changes in blood pressure, nausea, and dizziness.
Summary for NMDA antagonist
Prescription only
Amantadine is an NMDA antagonist. It's used to treat symptoms of movement disorders in adults, including Parkinson’s disease (PD). It works by raising the levels of dopamine in your body, which helps coordinate movements. Amantadine is taken by mouth, typically once or twice daily. Some side effects of this medication include nausea, dizziness, and trouble sleeping.