Drug Interaction Report

MONITOR: Coadministration with teriflunomide may increase the plasma concentrations and the risk of adverse effects of drugs that are substrates of the organic anion transporting polypeptide (OATP) 1B1 and 1B3 and/or breast cancer resistance protein (BCRP) transporters. The proposed mechanism, based on in vivo data, is decreased clearance due to teriflunomide-mediated inhibition of OATP 1B1/1B3 or BCRP transport proteins.

MANAGEMENT: Caution is advised if teriflunomide is used concomitantly with drugs that are substrates of OATP 1B1/1B3 and/or BCRP. Dosage adjustments as well as clinical and laboratory monitoring should be considered whenever teriflunomide is added to or withdrawn from therapy with these drugs. Patients should be monitored for the development of adverse effects.

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.