Drug Interaction Report

MONITOR: Theoretically, concomitant use of taurine and antihypertensive agents, vasodilators, or agents with hypotensive properties may have additive blood pressure-lowering effects. The proposed mechanism has not been established but has been suggested, primarily through studies in animal models, that taurine has a homeostatic function on vascular smooth muscle and cardiac muscle. Several mechanisms by which taurine has been proposed to promote vasodilation include effects on the nitric oxide system, endothelial function, and inhibition of the renin-angiotensin-aldosterone and sympathetic systems. A 2018 meta-analysis reviewing the effects of orally administered taurine on resting systolic blood pressure (SBP) and diastolic blood pressure (DBP) in humans showed that, in the 7 studies that met the inclusion criteria, treatment with oral taurine led to a statistically significant improvement in SBP and DBP compared with placebo. The mean reduction in blood pressure was approximately 3 mmHg for both systolic and diastolic readings, with a range of 0 to 15 mmHg and 0 to 7 mmHg for SBP and DBP, respectively. The effects of taurine supplementation may also be more significant in those who are pre-hypertensive or hypertensive compared to those with normal or moderately low blood pressure, regardless of their health status. However, clinical data are limited.

MANAGEMENT: Caution and monitoring for hypotension are recommended if oral taurine supplements are used in combination with antihypertensives, or agents with hypotensive properties. Patients should be advised to contact their physician if they experience symptoms of hypotension such as dizziness, lightheadedness, or fainting.

ADJUST DOSING INTERVAL: Food may reduce the oral bioavailability of silodosin. The effect of a moderate-fat, moderate-calorie meal on silodosin pharmacokinetics was variable and decreased silodosin maximum plasma concentration (Cmax) by approximately 18% to 43% and systemic exposure (AUC) by 4% to 49% across three different studies. The maximum effect of food (i.e., coadministration with a high-fat, high-calorie meal) on the pharmacokinetics of silodosin was not evaluated. Safety and efficacy clinical trials for silodosin were always conducted in the presence of food intake.

MANAGEMENT: Patients should be instructed to take silodosin with a meal to reduce the risk of adverse events.