Drug Interaction Report

MONITOR: Sapropterin may potentiate the hypotensive effects of vasodilators, including phosphodiesterase-5 (PDE5) inhibitors and drugs that affect nitric oxide-mediated vasodilation. Theoretically, the additive effects on vasodilation could lead to a reduction in blood pressure, although combined use of these medications has not been evaluated in humans. In animal studies, no effect on blood pressure was observed during coadministration of these agents.

MANAGEMENT: Caution is advised if sapropterin is used in combination with vasodilators, including topical drugs. Patients should be advised to contact their physician if they experience signs of hypotension such as dizziness, fainting, tachycardia, and headache.

ADJUST DOSING INTERVAL: Food increases the gastrointestinal absorption of sapropterin.

MANAGEMENT: Sapropterin should be administered with food, preferably at the same time each day. Sapropterin tablets should be dissolved in 4 to 8 ounces (120 to 240 mL) of water or apple juice and taken within 15 minutes of dissolution.