Sildenafil

DEA Class; Rx

Common Brand Names; Revatio, Viagra

• PAH, PDE-5 Inhibitors; 
• Phosphodiesterase-5 Enzyme Inhibitors

Oral, selective phosphodiesterase type 5 (PDE5) inhibitor
Used for pulmonary arterial hypertension (PAH) and erectile dysfunction (ED)
As with other PDE5 inhibitors, contraindicated for use with nitrates because the combination can cause a sudden drop in blood pressure

Indicated For the treatment of erectile dysfunction (ED).

Hypersensitivity

Soluble guanylate cyclase (sGC) stimulators (eg, riociguat); concomitant use can cause hypotension

>10%

Viagra

• 25-mg dose

  • Headache (16%)

• 50-mg dose

  • Headache (21%)
  • Flushing (19%)
  • 100-mg dose H5
  • Headache (28%)
  • Flushing (18%)
  • Dyspepsia (17%)
  • Abnormal vision (11%)

• Revatio

  • Headache (46%)
  • Dyspepsia (13%)

1-10%

Viagra

• 25-mg dose

  • Flushing (10%)
  • Nasal congestion (4%)
  • Dyspepsia (3%)
  • Back pain (3%)
  • Dizziness (3%)
  • Myalgia (2%)
  • Nausea (2%)
  • Abnormal vision (1%)
  • Rash (1%)

• 50-mg dose

  • Dyspepsia (9%)
  • Nasal congestion (4%)
  • Back pain (4%)
  • Dizziness (4%)
  • Nausea (3%)
  • Abnormal vision (2%)
  • Myalgia (2%)
  • Rash (2%)

• 100-mg dose

  • Nasal congestion (9%)
  • Back pain (4%)
  • Myalgia (4%)
  • Nausea (3%)
  • Dizziness (3%)
  • Rash (3%)

Elicits vasodilatory properties, resulting in mild and transient decreases in blood pressure

Use with caution in patients with anatomic deformation of penis (eg, angulation, cavernosal fibrosis, or Peyronie disease), conditions potentially predisposing to priapism (eg, sickle cell anemia, multiple myeloma, or leukemia), cardiovascular disease, bleeding disorders, active peptic ulcer disease, liver disease, renal impairment, multidrug antihypertensive regimens, retinitis pigmentosa, concomitant use of CYP3A4 inhibitors

Pulmonary vasodilators may significantly worsen cardiovascular status of patients with pulmonary veno-occlusive disease

Patient taking alpha blocker should be stabilized before starting phosphodiesterase (PDE)-5 inhibitor, which should be initiated at lowest dose; if patient is already taking optimized dose of PDE-5 inhibitor, alpha blocker should be initated at lowest dose to avoid hypotension

Not to be taken with other PDE-5 inhibitors

Sudden decrease or loss of hearing, which may be accompanied by tinnitus and dizziness

Viagra: Patients should stop sildenafil and seek medical care if a sudden loss of vision occurs in 1 or both eyes, which could be a sign of nonarteritic anterior ischemic optic neuropathy (NAION); use with caution, and only when the anticipated benefits outweigh the risks, in patients with a history of NAION; patients with a ”crowded” optic disc may also be at an increased risk of NAION; advise patients to seek immediate medical attention in the event of a sudden loss of vision

Viagra: Potential for cardiac risk with sexual activity in patients with preexisting cardiovascular disease; therefore, treatment for erectile dysfunction generally should not be instituted in men for whom sexual activity is inadvisable because of their underlying cardiovascular status

Pregnant women with untreated pulmonary arterial hypertension are at risk for heart failure, stroke, preterm delivery, and maternal and fetal death

Limited published data from a case report describe presence of sildenafil and its active metabolite in human milk

Sildenafil citrate

tablet (Revatio)

• 20mg

tablet (Viagra)

• 25mg
• 50mg
• 100mg

injectable solution (Revatio)

• 10mg/12.5mL

oral suspension (Revatio)

• 10mg/mL (when reconstituted)