Gallopamil slow release: a double blind study of twice daily versus once daily treatment in chronic stable angina
The clinical efficacy of a new slow release preparation of the calcium antagonist gallopamil was assessed in 20 patients by diary cards and treadmill exercise tests. A single blind phase of two week periods of placebo, gallopamil 100 mg o.d. and gallopamil 100 mg b.i.d., blinded to the patient, was followed in 18 patients by a double blind comparison of gallopamil 100 mg od versus 100 mg b.i.d. Angina frequency and trinitrin consumption per week were both significantly less on high dose (2.7 and 1.7) than on low dose (5.4 and 3.4) respectively. Treadmill total exercise time was longer on high dose (523 s) than low dose (449 s). Other exercise test parameters showed similar improvements on high dose treatment. Gallopamil was well tolerated. PR interval correlated best with plasma gallopamil level, while exercise test parameters correlated best with the log plasma level of its major metabolite nor-gallopamil.