1. The effects of 160 mg of propranolol and 160 mg of a long-acting (LA) formulation of propranolol were studied in healthy subjects.
2. Both drugs reduced an exercise tachycardia but the peak was less and the 24 h effect greater after long-acting propranolol than after propranolol.
3. These differences were maintained on repeated dosing for 8 days.
4. In contrast to single doses of 400 mg of sotalol, 160 mg of oxprenolol and 160 mg of slow-release oxprenolol, the peak effect of long-acting propranolol was less and that at 24 h was greater.