Alpha-Blocker and PDE5 Inhibitor Interactions

Critical Drug-Specific Interactions

• The American College of Cardiology notes that terazosin is associated with orthostatic hypotension, especially in older adults, and this risk is compounded when combined with PDE5 inhibitors 1
• The American College of Cardiology and other guidelines suggest that prazosin carries the same risks as other non-selective alpha-1 blockers when combined with PDE5 inhibitors, and is associated with orthostatic hypotension, especially in elderly patients, and requires 2-3 times daily dosing 1, 2

Clinical Management Algorithm

• The American College of Cardiology recommends avoiding combination therapy entirely in elderly patients or those with baseline orthostatic hypotension when using alpha-blockers and PDE5 inhibitors 1