Drug Interaction Report

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.

GENERALLY AVOID: Moderate-to-high dietary intake of potassium, especially salt substitutes, may increase the risk of hyperkalemia in some patients who are using angiotensin II receptor blockers (ARBs). ARBs can promote hyperkalemia through inhibition of angiotensin II-induced aldosterone secretion. Patients with diabetes, heart failure, dehydration, or renal insufficiency have a greater risk of developing hyperkalemia.

MANAGEMENT: Patients should receive dietary counseling and be advised to not use potassium-containing salt substitutes or over-the-counter potassium supplements without consulting their physician. If salt substitutes are used concurrently, regular monitoring of serum potassium levels is recommended. Patients should also be advised to seek medical attention if they experience symptoms of hyperkalemia such as weakness, irregular heartbeat, confusion, tingling of the extremities, or feelings of heaviness in the legs.