Selegiline is a medication with a complex profile, and its brand names are tied directly to its method of delivery and intended use. As a monoamine oxidase inhibitor (MAOI), selegiline increases levels of neurotransmitters in the brain, but the specific type of monoamine oxidase it affects can change depending on the dosage and route of administration.
Brand Names and Formulations
Eldepryl and Generic Selegiline (Oral Capsules/Tablets)
Eldepryl was one of the first brand names for oral selegiline, though the original brand-name capsule is no longer available. Generic selegiline capsules and tablets are still used today. This form is typically prescribed as an adjunct therapy for Parkinson's disease, used alongside levodopa to help manage motor symptoms like tremors and stiffness. The oral route is associated with extensive first-pass metabolism, resulting in higher levels of amphetamine-related metabolites compared to other forms.
Zelapar (Orally Disintegrating Tablets)
Zelapar is an orally disintegrating tablet (ODT) formulation of selegiline, also used for treating Parkinson's disease. Unlike traditional capsules, Zelapar dissolves on the tongue and is absorbed directly, bypassing some of the first-pass metabolism that affects the oral capsules. This results in a different metabolite profile and altered bioavailability compared to the standard oral form. The ODT is typically taken once daily in the morning without water, and patients are advised to avoid eating or drinking for a short period before and after taking it.
Emsam (Transdermal Patch)
Emsam is the brand name for the selegiline transdermal patch. It is specifically approved for the treatment of major depressive disorder (MDD) in adults. The patch is applied to the skin once daily and provides a continuous, sustained release of the medication over 24 hours. This transdermal delivery route results in substantially higher exposure to selegiline and lower levels of its metabolites compared to oral dosing. At the lowest dose (6 mg/24 hours), the patch can be used without the strict dietary restrictions typically required for MAOIs, though higher doses necessitate some food limitations.
How Selegiline Works
Selegiline's primary mechanism of action is the selective, irreversible inhibition of monoamine oxidase B (MAO-B). The MAO-B enzyme is responsible for breaking down dopamine in the brain. By inhibiting this enzyme, selegiline increases the amount of dopamine available in the brain, which helps to alleviate the motor symptoms of Parkinson's disease.
At higher doses, or when administered transdermally (e.g., with the Emsam patch), selegiline can lose its selectivity and also inhibit monoamine oxidase A (MAO-A). This broader inhibition affects other neurotransmitters, like norepinephrine and serotonin, which contributes to its antidepressant effects but also increases the risk of serious side effects and drug-food interactions.
Comparison of Selegiline Formulations
| Feature | Eldepryl (Oral Capsule) / Generic | Zelapar (Orally Disintegrating Tablet) | Emsam (Transdermal Patch) |
|---|---|---|---|
| Primary Use | Adjunct for Parkinson's disease | Adjunct for Parkinson's disease | Major depressive disorder |
| Route | Oral (capsule or tablet) | Oral (dissolves on tongue) | Transdermal (applied to skin) |
| Bioavailability | 4%–10% (low) | 5–8x higher than oral capsule | 75% (high) |
| Metabolites | High levels due to first-pass metabolism | Significantly lower levels than oral capsule | Significantly lower levels than oral capsule |
| Dietary Restrictions | Needed at higher doses (over 10mg/day) | Needed at higher doses (over 2.5mg/day) | Not required at 6mg/day; strict restrictions at 9mg or 12mg/day |
| Key Advantage | Established use for Parkinson's | Improved absorption; avoids swallowing issues | Bypasses first-pass metabolism; high bioavailability; lower metabolite levels |
Safety Considerations and Drug Interactions
Regardless of the brand name, selegiline treatment requires careful consideration due to its potential for serious side effects and interactions. The risk of side effects increases with higher doses and with the use of the transdermal patch due to its non-selective MAO inhibition.
- Hypertensive Crisis: When selegiline non-selectively inhibits MAO (at higher doses or transdermally), it can interact with tyramine-rich foods (e.g., aged cheese, cured meats, sauerkraut) to cause a dangerous spike in blood pressure. Patients on higher doses of selegiline must follow strict dietary guidelines.
- Serotonin Syndrome: Combining selegiline with other serotonergic medications, such as SSRIs, can lead to a rare but life-threatening condition called serotonin syndrome. Symptoms can include agitation, hallucinations, rapid heartbeat, and confusion. A wash-out period is often necessary when switching medications.
- Other Interactions: Selegiline interacts with numerous medications, including certain opioids (like meperidine), some antidepressants, stimulants, and certain cold and allergy medicines. A healthcare provider must be informed of all medications and supplements being taken.
Conclusion
In summary, the generic name is selegiline, but the specific brand name depends on the delivery method and the medical condition being treated. Eldepryl (or generic oral capsules/tablets) and Zelapar (orally disintegrating tablets) are used for Parkinson's disease, while Emsam (transdermal patch) is for major depressive disorder. Each formulation offers distinct advantages and safety profiles related to its unique bioavailability and metabolic pathways. Understanding these differences is crucial for effective and safe treatment with selegiline.
This article is for informational purposes only and is not a substitute for professional medical advice. Always consult with a qualified healthcare provider for any health concerns or before making any decisions related to your treatment.
