Table 23Parenteral drugs for treatment of hypertensive emergencies*

DrugDoseOnset of ActionDuration of ActionAdverse EffectsSpecial Indications
Sodium nitroprusside0.25–10 μg/kg/min as IV infusionImmediate1–2 minNausea, vomiting, muscle twitching, sweating, thiocynate and cyanide intoxicationMost hypertensive emergencies; caution with high intracranial pressure or azotemia
Nicardipine hydrochloride5–15 mg/h IV5–10 min15–30 min, may exceed 4 hrsTachycardia, headache, flushing, local phlebitisMost hypertensive emergencies except acute heart failure; caution with coronary ischemia
Fenoldopam mesylate0.1–0.3 μg/kg per min IV infusion<5 min30 minTachycardia, headache, nausea, flushingMost hypertensive emergencies; caution with glaucoma
Nitroglycerin5–100 μg/min as IV infusion2–5 min5–10 minHeadache, vomiting, methemoglobinemia, tolerance with prolonged useCoronary ischemia
Enalaprilat1.25–5 mg every 6 hrs IV15–30 min6–12 hrsPrecipitous fall in pressure in high-renin states; variable responseAcute left ventricular failure; avoid in acute myocardial infarction
Hydralazine hydrochloride10–20 mg IV
10–40 mg IM
10–20 min IV
20–30 min IM
1–4 hrs IV
4–6 hrs IM
Tachycardia, flushing, headache, vomiting, aggravation of anginaEclampsia
Adrenergic Inhibitors
Labetalol hydrochloride20–80 mg IV bolus every 10 min 0.5–2.0 mg/min IV infusion5–10 min3–6 hrsVomiting, scalp tingling, bronchoconstriction, dizziness, nausea, heart block, orthostatic hypotensionMost hypertensive emergencies except acute heart failure
Esmolol hydrochloride250–500 μg/kg/min IV bolus, then 50– 100 μg/kg/min by infusion; may repeat bolus after 5 min or increase infusion to 300 μg/min1–2 min10–30 minHypotension, nausea, asthma, first degree heart block, heart failureAortic dissection, perioperative
Phentolamine5–15 mg IV bolus1–2 min10–30 minTachycardia, flushing, headacheCatecholamine excess

h or hr, hour; IM, intramuscular; IV, intravenous; min, minute(s)

* These doses may vary from those in the Physicians' Desk Reference (51st ed.)

Hypotension may occur with all agents

Require special delivery system

From: Special Situations in Hypertension Management

Cover of The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure
The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure.
National High Blood Pressure Education Program.

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