Deprenyl: www.antiaging-systems.com/50-deprenyl otherwise known as Selegiline is primarily used to treat the symptoms of Parkinson's disease, because Deprenyl helps to improve brain levels of Dopamine, the neurotransmitter that is most affected by that disease. Whilst dosages in the treatment of Parkinson's disease can often be 20 mg. a day or higher, those utilizing deprenyl for an anti-aging program are more likely to use just a few milligrams daily.