Terazosin Effect on Cardiac Changes in Early Parkinson's Disease

Fifteen patients with defined pre-motor PD risk and abnormal baseline 123I-MIBG uptake, with or without 123I-Ioflupane uptake abnormality or PD motor symptoms, will be recruited to receive daily oral doses of terazosin 5 mg or 10 mg. The dosage of terazosin will be gradually increased from the initial recommended starting dose of 1 mg daily at bedtime and titrated stepwise to 2mg, 5mg or 10 mg weekly, according to patient tolerability, as measured by subjective complaints, arterial blood pressure and heart rate. The target dose will be 5 mg or 10 mg daily based on subject's tolerability. Development of incompatibility will be addressed by individually adjusting the dose of terazosin.