01
Nitrate interaction
PDE5 inhibitors combined with nitrates (nitroglycerin, isosorbide mononitrate/dinitrate, and recreational “poppers”) can cause a severe, potentially fatal drop in blood pressure. This combination is contraindicated.
Safety
ED Medication Safety
The interactions and warning signs every person considering an ED treatment should understand.
Seek emergency care immediately for:
- • Chest pain, pressure or irregular heartbeat
- • Severe dizziness or fainting
- • Sudden vision loss
- • Sudden hearing loss
- • An erection lasting more than 4 hours
- • Signs of a severe allergic reaction
02
Riociguat interaction
Riociguat and other guanylate cyclase stimulators used for pulmonary hypertension are contraindicated with PDE5 inhibitors for the same reason.
03
Alpha-blocker precautions
Alpha-blockers for blood pressure or prostate symptoms are not universally contraindicated, but combined use can cause dizziness or fainting. A clinician should guide dosing and timing.
04
Cardiovascular considerations
Sexual activity places demand on the heart. People with recent heart attack or stroke, unstable angina, severe heart failure, or uncontrolled blood pressure need medical assessment first.
05
Other drug interactions
Strong CYP3A4 inhibitors (some antifungals, HIV medications, certain antibiotics) raise PDE5-inhibitor levels. Grapefruit can have a similar effect.
06
Priapism
An erection lasting more than four hours can permanently damage tissue. It is a medical emergency.
07
Vision changes
Sudden loss of vision in one or both eyes has rarely been reported (NAION). Stop use and seek urgent care.
08
Hearing changes
Sudden decrease or loss of hearing, sometimes with ringing or dizziness, has been reported. Stop use and seek urgent care.
09
Counterfeit medication risks
Counterfeit pills may contain the wrong drug, the wrong dose, or contaminants—and skip the interaction screening a prescriber provides.
10
Unverified supplement risks
Supplements marketed for sexual performance have repeatedly been found to contain hidden prescription drugs at unknown doses.