Medicine & USMLE

Hydralazine (Old)

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Hydralazine is a vasodilating drug that works to lower blood pressure in order to treat severe hypertension. An important side effect is reflex tachycardia, which is why hydralazine is often administered with beta blockers. The patient’s heart rate and blood pressure should be monitored before every dose of hydralazine.

Key Points

  • Mechanism
    • Vasodilator
      • Relaxes the blood vessels, allowing for vasodilation and thus lowering the blood pressure
    • Clinical Use
      • Severe hypertension, acute onset
        • Hypertension with preeclampsia
        • Hypertensive crisis
      • Heart failure
        • Used in combination with a nitrate
    • Side Effects and Adverse Reactions
      • Hypotension
        • Reflex tachycardia
          • Often given in conjunction with beta blockers to prevent against reflex tachycardia
          • Can commonly lead to palpitations
          • Heart rate and blood pressure should be monitored before every administration
        • Dizziness
      • Hepatotoxicity
      • Headache
      • GI distress
        • Nausea/vomiting, diarrhea, anorexia
        • GI bleeding