BETA BLOCKERS AND PHENOBARBITAL
The plasma levels and the effects of beta blockers that are mainly metabolised in the liver (e.g. alprenolol, metoprolol, timolol) are reduced by the barbiturates. Alprenolol concentrations are halved, but the others are possibly not affected as much.
Monitor concurrent use to ensure these beta blockers are effective. Beta blockers that are mainly excreted unchanged in the urine (e.g. atenolol, sotalol, nadolol) would not be expected to be affected by the barbiturates.
Monitor concurrent use to ensure these beta blockers are effective. Beta blockers that are mainly excreted unchanged in the urine (e.g. atenolol, sotalol, nadolol) would not be expected to be affected by the barbiturates.