Calcium antagonists (CaAs) are divided into three structural classes, typically represented by verapamil, diltiazem and nifedipine. As a group, the principal (type I) adverse effects of these drugs relate to the pharmacological action of calcium channel blockade, namely vasodilation, and include dizziness, flushing, palpitations and peripheral oedema. The clinical safety of the new dihydropyridine CaA, barnidipine, has been assessed in more than 12 clinical trials, including 2041 patients who have been treated with one or more doses of barnidipine (dose of up to 50 mg). Adverse events with barnidipine are of mild to moderate intensity, most commonly of type I, occurring in the early phase of treatment. The incidence of serious adverse events and the rate of withdrawals are low. Hence, barnidipine is likely to be well tolerated in general clinical use.