Comparison of effects of two dosage regimens of phenylpropanolamine on blood pressure and plasma levels in normal subjects under steady-state conditions.
Plasma levels and blood pressure responses to two dosage regimens of phenylpropanolamine (PPA)-25-mg, immediate-release tablets three times per day and a 75-mg, controlled-release capsule once per day--were compared in 14 normal subjects. To obtain steady-state conditions, subjects were given the test materials for four-day periods, and blood pressure and plasma PPA levels were measured on day 4. The dosage forms were equally bioavailable, based on a 95-percent confidence coefficient, and neither produced hypertensive effects. The highest diastolic pressure was 96 mm Hg three hours after a 25-mg dose. Mean PPA plasma levels showed no correlation with mean blood pressure readings at any point during a 12-hour test period. These data show that, in these subjects, a daily dosage of PPA 75 mg, either in divided doses of 25 mg each or in a dependable controlled-release formula, produces no indication of pressor effects.
D000284:Administration, Oral; D000328:Adult; D001682:Biological Availability; D001794:Blood Pressure / Q000187:drug effects*; D003692:Delayed-Action Preparations; D006801:Humans; D008297:Male; D010665:Phenylpropanolamine / Q000008:administration & dosage* / Q000097:blood; D013607:Tablets; D013997:Time Factors
D003692:Delayed-Action Preparations; D013607:Tablets; D010665:Phenylpropanolamine