Sildenafil / Vardenafil

Mechanism

• cGMP phosphodiesterase inhibitor
  • results in less cGMP degradation and ↑ cGMP 
• Drives smooth muscle relaxation in the corpus cavernosum
• ↑ blood flow to penis

Indications

• Erectile dysfunction
• Pulmonary hypertension

Toxicity

• Side effects
  • headache
  • flushing
  • dyspepsia
  • impaired blue-green color vision
• Do not co-administer with nitrates
  • risk of life-threatening hypotension