used to help control the symptoms of Parkinson's disease in people who are taking levodopa and carbidopa combination (Sinemet). Selegiline may help people with PD by stopping the effects of levodopa/carbidopa from wearing off, and increasing the length of time levodopa/carbidopa continues to control symptoms. Rasagiline In response to potentially toxic amphetamine metabolites caused by selegiline, another promising treatment is in MAO B propargyl amine inhibitor rasagiline (N-propargyl-1-R-aminoindan, Azilect((R))). The oral bioavailability of rasagiline is 35%, it reaches T(max) after 0.5–1.0 hours and its half-life is 1.5–3.5 hours. Rasagiline undergoes extensive hepatic metabolism primarily by cytochrome P450 type 1A2 (CYP1A2). Rasagiline is initiated at 1-mg once-daily dose as monotherapy in early PD patients and at 0.5–1.0 mg once-daily as adjunctive to levodopa in advanced PD patients. Neural transplantation Since early in the 1980s fetal, porcine, carotid or retinal tissues have been used in cell transplants for PD patients. Although there was initial evidence of mesencephalic dopamine-producing cell transplants being beneficial, the best constructed studies up to date indicate that cell transplants have no effect. An additional significant problem was the excess release of dopamine by the transplanted tissue, leading to dystonias. Stem cell transplants are a main research recent target: they are easy to manipulate and when transplanted into the brains of rodents and monkeys, cells survive and improve behavioral abnormalities of the animals. Nevertheless, use of fetal stem cells is controversial. Some have proposed that such controversy may be overcome with the use of induced pluripotent stem cells from adults. References External links Parkinson's Medication Chart at the Parkinson's Disease Foundation PDtrials Find What Treatments Are Possible Parkinson's disease