The effects of combining felodipine and metoprolol in moderate to severe hypertension--a one year study.

A dose titration study was performed using felodipine, a new calcium antagonist, in Chinese patients with essential hypertension inadequately controlled by metoprolol alone (DBP greater than 95 mmHg). BP and pulse rate were recorded at rest and during treadmill exercise. Nineteen patients completed the six weeks' dose titration phase (2.5-5-10 mg twice daily) of whom 17 were followed for one year. A single 2.5 mg dose of felodipine produced a rapid and pronounced antihypertensive response with pre-exercise supine BP falling from a mean 168/104 to 146/92 mmHg) (P less than 0.001). The SBP during exercise was reduced from 206 to 185 mmHg (P less than 0.001). After 6 weeks treatment the supine BP had fallen to 132/85 mmHg (P less than 0.001) and the SBP during exercise to 169 mmHg (P less than 0.001). Six patients received 2.5 mg twice daily, eight patients 5 mg twice daily and three patients 10 mg twice daily. The effects, both at rest and during exercise, were maintained for at least 12 hours after dosing. The pulse rate was unaffected by felodipine therapy apart from a small transient increase following the first dose. Sixteen patients achieved the target DBP of 90 mmHg measured 12 hours after dosing and only one patient still had a DBP greater than 95 mmHg. After one year the mean supine BP had fallen slightly further to 128/82 mmHg. One patient was withdrawn due to palpitations. Felodipine was otherwise well tolerated.(ABSTRACT TRUNCATED AT 250 WORDS)