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Diltiazem

Brand: Cardizem

Calcium channel blockerUsed for: High blood pressure, rate controlCardiovascular
Key warning

Caution: can worsen certain heart failure or heart-block conditions

Common side effects

  • Swelling of ankles or feet
  • Dizziness
  • Slow heart rate
  • Constipation
  • Headache

Key interactions & cautions

  • Adds to heart slowing with beta-blockers
  • Grapefruit juice raises drug levels
  • May raise statin levels (simvastatin)
  • Caution with other blood pressure drugs

Counseling points

  • Take at the same time each day
  • Do not crush extended-release tablets
  • Rise slowly to reduce dizziness
  • Report swelling, fainting, or very slow pulse
  • Avoid grapefruit juice

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