The antiparkinsonian actions and pharmacokinetics of transdermal (+)‐4‐Propyl‐9‐hydroxynaphthoxazine (+ PHNO): Preliminary results

Abstract

Abstract(+)‐4‐Propyl‐9‐hydroxynaphthoxazine (+ PHNO) is a potent dopamine agonist that has been administered transdermally to four patients with Parkinson's disease and “on‐off” fluctuations. Skin patches of increasing size were used to treat these patients, who also received infrequent doses of oral levodopa if required. The effect of +PHNO was measured as an increased duration of action of individual levodopa doses. The clinical effect measured in this way was directly proportional to the plasma concentrations of +PHNO achieved. The plasma concentrations of + PHNO began to rise 4–6 h after patch application and reached a steady state by 24 h. The final plasma concentration of + PHNO was proportional to the area of skin covered.