Drug Interactions between levobetaxolol ophthalmic and Sensorcaine-MPF with Epinephrine

MONITOR: Beta-blockers may increase the risk of bupivacaine-induced side effects. The proposed mechanism is increased bupivacaine levels due to hepatic enzyme inhibition (propranolol) and/or additive negative inotropic effects on the heart. Patients with heart failure may be at a greater risk. Data have been conflicting and variable. Theoretically, beta-blocker ophthalmic solutions may also interact, as they are systemically absorbed and can produce clinically significant systemic effects even at low or undetectable plasma levels.

MANAGEMENT: Caution is recommended if multiple doses of bupivacaine are administered in the presence of a beta-blocker. Monitoring for drowsiness, mental status changes, convulsions, ECG changes, and hypotension is advisable during concurrent therapy.

MONITOR: Beta-blockers may antagonize the cardiostimulatory effects of pressor agents by blocking beta-1 adrenergic receptors in the heart. Vasopressors may be less effective if the patient is receiving, or has recently received, a beta-blocking drug. In addition, peripheral vascular resistance may increase due to unopposed alpha-adrenergic effects of pressor agents in the presence of beta-blockade. Theoretically, the interaction may also occur with beta-blocker ophthalmic preparations, since they may be systemically absorbed and can produce clinically significant systemic effects even at low or undetectable plasma levels.

MANAGEMENT: No specific intervention is necessary, but clinicians should be alert to the potential for diminished cardiac response when pressor agents are used in patients treated with beta-blockers, including ophthalmic formulations. A beta-blocker such as propranolol may be used to treat cardiac arrhythmias that occur during administration of pressor agents like mephentermine, metaraminol, norepinephrine, or phenylephrine.