No subjects experienced adverse effects during the infusion although one vomited after discontinuation of L-dopa. For one dosage and rate: change in AVP (plasma arginine vasopressin), blood pressure and heart rate are given. No significant effects of L-Dopa on mean blood pressure in normal subjects, but lowered blood pressure of MSA patients. No effect heart rate or AVP levels in basal state. Author suggests “L-Dopa should not be prescribed for patients with MSA”. This evidence concerns the gene AVP and multiple system atrophy.