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Promethazine

Brand: Phenergan

Antiemetic / antihistamineUsed for: Nausea and vomitingGastrointestinal
Key warning

Boxed warning: fatal respiratory depression in children under 2 — contraindicated in that age group. (The separate INJECTABLE form carries its own boxed warning for severe tissue injury including gangrene; that one is not part of the oral labeling.)

Common side effects

  • Drowsiness
  • Dry mouth
  • Dizziness
  • Low blood pressure
  • Blurred vision

Key interactions & cautions

  • Alcohol increases sedation
  • Adds to other sedating drugs
  • Adds to opioid sedation

Counseling points

  • May cause marked drowsiness
  • Do not drive until you know its effect
  • Avoid alcohol
  • Report muscle stiffness or high fever
  • Rise slowly to reduce dizziness

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