Drug reference
sildenafil
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Drug class
Genitourinary (Vasodilator)
Mechanism of action
Inhibits PDE-5, increasing cyclic guanosine monophosphate cGMP to allow smooth-muscle relaxation. Duration of action: 4-5 hours
Common side effects
- Dyspepsia
- Headache
Contraindications
- Hypersensitivity Soluble guanylate cyclase (sGC) stimulators (eg, riociguat); concomitant use can cause hypotension Coadministration with nitrates Coadministration with nitrates (either regularly and/or intermittently) and nitric oxide donors Consistent with the effects of PDE5 inhibition…
Known interactions (6)
- isosorbide dinitrate + sildenafil Contraindicated
- isosorbide mononitrate + sildenafil Contraindicated
- nitroglycerin + sildenafil Contraindicated
- riociguat + sildenafil Contraindicated
- prazosin + sildenafil Major
- ritonavir + sildenafil Major
Related conditions
Frequently asked questions
What drug class is sildenafil?
sildenafil belongs to: Genitourinary.
How does sildenafil work?
Inhibits PDE-5, increasing cyclic guanosine monophosphate cGMP to allow smooth-muscle relaxation. Duration of action: 4-5 hours
What are the common side effects of sildenafil?
Dyspepsia, Headache
Which drugs interact with sildenafil?
isosorbide dinitrate, isosorbide mononitrate, nitroglycerin, riociguat, prazosin, ritonavir
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