PEBC: What You Need to Know: PDE-5 Inhibitors

Examples:

sildenafil, vardenafil, tadalafil

Indication:

Erectile Dysfunction

Dosing:

-30 to 60 minutes prior to the event. Stimulation is required for efficacy.

-Do not exceed 1 tablet per day

Duration of Action:

-Tadalafil has a very long duration of action (up to 72 hours) compared to sildenafil and vardenafil (4 hours)

Adverse Effects:

-Dizziness

-Visual disturbances such as blurry vision

-Facial flushing

-Priapism - erection which does not resolve within four hours **may need medical attention

-Muscle aches

-Nasal congestion

Drug Interactions:

-Do not combine with nitrates - could lead to fatal hypotension. Make sure to space nitrate after 24 hours for sildenafil or vardenafil, and 48 hours for tadalafil.

-alpha blockers and antihypertensives: dizziness and hypotension

-CYP 3A4 inhibitors such as ketoconazole since PDE5 inhibitors are substrates