Abstract
Calcium antagonists demonstrate a close relationship between plasma drug level and effect on blood pressure (BP). Thus, the intensity and duration of action can be influenced by dose and disposition. Felodipine has a dose-related effect on diastolic BP whether given alone or with a beta-blocker. The latter combination reduces adverse effects and improves tolerability, particularly at higher (20 mg/day) doses of felodipine. Felodipine 5 or 10 mg/day in an extended release formulation could be predicted to lower BP throughout a 24-h period. The results of formal prospective clinical trials confirm the predictions and indicate that felodipine can be used as a once-daily agent in essential hypertension.