Hydralazine (Apresoline)


  • Miscellaneous


  • Antihypertensive; (preferentially dilates arterioles)


  • Hypertension


  • Coronary artery disease

  • Valvular rheumatic heart disease


  • Pregnancy category C

  • Advanced renal disease, children, pulmonary hypertension

Adverse Reactions (Side Effects):

  • CNS: anxiety, dizziness, headache, peripheral neuritis, psychotic reactions, tremor

  • CV: angina, edema, flushing, hypotension, palpitations, reflex tachycardia

  • EENT: nasal congestion

  • GI: anorexia, constipation, diarrhea, hepatitis, paralytic ileus, nausea, vomiting

  • GU: urination difficulty

  • HEME: agranulocytosis, anemia, eosinophilia, leukopenia

  • SKIN: pruritis, rash, urticaria

  • MISC: lupus-like syndrome, arthralgia, muscle cramps


Administered orally (tablet), intramuscularly, and intravenously

  • Adult:   

    • PO 10mg 4 times daily, increase by 10-25 mg/dose every 2-5 days as needed to max of 300 mg/day

    • IM/IV 10-20mg every 4-6 hours, may increase to 40 mg/dose

  • Child:   

    • PO 0.75-1 mg/kg/day divided 2-4 times daily, increase over 3-4 weeks to 7.5 mg/kg/day divided 2-4 times daily if necessary, do not exceed 200 mg/day

    • IM/IV 0.1-0.2 mg/kg/dose every 4-6 hours, do not exceed 20 mg/dose

Special Considerations:

  • May cause black stools

  •  Take with meals

  •  Lupus-like syndrome more common in “slow acetylators” and folling higher doses for prolonged periods

  •  Patient to notify clinician of any unexplained prolonged general tiredness, or fever, muscle or joint aching, or chest pain

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