We have studied a cohort of 220 Parkinson's disease (PD) patients for risk factors of developing new dyskinesia. Twenty-nine patients were noticed to have developed new dyskinesia at the second assessment. The dyskinetic patients received significantly higher maximum level daily dose of levodopa. These patients had lost weight during the course of the disease from 72+/-15 to 66+/-17kg, p=0.002. The dyskinetic patients received significantly higher daily dose of levodopa per kilogram body weight, 8.4+/-3.5mg/kg vs. 6.0+/-3.9mg, p=0.003. Weight-losers PD patients developed significantly more dyskinesia than non-weight losers-p=0.002. Logistic regression analysis revealed weight loss and daily levodopa dose per kilogram body weight to be the only significant factors for dyskinesia in addition to disease duration. There was a "dose response to developing dyskinesia" according to the increasing levodopa dose per kilogram body weight.