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Sildenafil Citrate

Also sold as SILDENAFIL CITRATE, Sildenafil, Viagra

Medicine summary · from official FDA labels · Oct 19, 2026

What it’s used for

Sildenafil tablets are indicated for the treatment of erectile dysfunction.

How to take it

For most patients, the recommended dose is 50 mg taken, as needed, approximately 1 hour before sexual activity. However, sildenafil tablets may be taken anywhere from 30 minutes to 4 hours before sexual activity ( 2.

Important warnings

Patients should not use sildenafil if sexual activity is inadvisable due to cardiovascular status ( 5. 1 ) Patients should seek emergency treatment if an erection lasts >4 hours.

Common side effects

The following are discussed in more detail in other sections of the labeling: Cardiovascular [ see Warnings and Precautions (5. 1) ] Prolonged Erection and Priapism [ see Warnings and Precautions (5.

Interactions

Sildenafil can potentiate the hypotensive effects of nitrates, alpha blockers, and anti-hypertensives ( 4.

If pregnant or breastfeeding

8.

Forms & strengths

10 MG/ML Oral Suspension · 50 MG Oral Tablet · 25 MG Oral Tablet · 100 MG Oral Tablet · 20 MG Oral Tablet

Questions to ask your doctor or pharmacist

  • Is this the right medicine for my condition, and how long should I take it?
  • What side effects should I watch for, and which need urgent attention?
  • Does this interact with my other medicines, supplements, or alcohol?
  • What should I do if I miss a dose or take too much?