Bioavailability and clinical effects of three brands of clonidine: the relationship between plasma level and effect

The bioavailability and effect on the systolic and diastolic blood pressure, heart rate, salivary flow, skin temperature, and subjective sedation of three brands of clonidine were studied in nine healthy volunteers after a single 300-micrograms oral dose. In the gas chromatographically determined plasma concentrations there was no significant difference, nor was there any difference in the clinical effects studied. Highly significant correlations between the plasma concentrations and drug effects were found.