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Sildenafil

Brand: Viagra

PDE5 inhibitorUsed for: Erectile dysfunction (avoid with nitrates)Other High-Yield
Key warning

Caution: combining with nitrates can cause a fatal drop in blood pressure

Common side effects

  • Headache
  • Flushing
  • Nasal congestion
  • Indigestion
  • Visual color changes

Key interactions & cautions

  • Do not use with nitrates; dangerous drop in blood pressure
  • Alpha-blockers can add to low blood pressure
  • Certain antifungals and HIV drugs raise its levels

Counseling points

  • Take about an hour before activity
  • Do not take with nitrate heart medicines
  • Rise slowly to reduce dizziness
  • Seek care for erection lasting over 4 hours
  • Report sudden vision or hearing loss

High-yield study aid for exam prep — not a substitute for the package insert or a pharmacist’s dispensing reference.