Diazoxide IV
Diazoxide IV (Hyperstat IV)
Diazoxide IV
(dye-az- OX-eyed)
Pregnancy Category: C Hyperstat IV (Rx)

Classification: Antihypertensive, direct action on vascular smooth muscle

See Also: See also Antihypertensive Agents and Diazoxide Oral .

Action/Kinetics: Exerts a direct action on vascular smooth muscle to cause arteriolar vasodilation and decreased peripheral resistance. Onset: 1-5 min. Time to peak effect: 2-5 min. Duration (variable): usual, 3-12 hr. Excreted through the kidney (50% unchanged).

Uses: May be the drug of choice for hypertensive crisis (malignant and nonmalignant hypertension) in hospitalized adults and children. Often given concomitantly with a diuretic. Especially suitable for clients with impaired renal function, hypertensive encephalopathy, hypertension complicated by LV failure, and eclampsia. Ineffective for hypertension due to pheochromocytoma.

Contraindications: Hypersensitivity to drug or thiazide diuretics. Treatment of compensatory hypertension due to aortic coarctation or AV shunt. Dissecting aortic aneurysm.

Special Concerns: A decrease in dose may be necessary in geriatric clients due to age-related decreases in renal function. If given prior to delivery, fetal or neonatal hyperbilirubinemia, thrombocytopenia, or altered carbohydrate metabolism may result. Use with caution during lactation and in clients with impaired cerebral or cardiac circulation.

Side Effects: CV: Hypotension (may be severe enough to cause shock), sodium and water retention, especially in clients with impaired cardiac reserve, atrial or ventricular arrhythmias, cerebral or myocardial ischemia marked ECG changes with possibility of MI palpitations, bradycardia, SVT, chest discomfort or nonanginal chest tightness. CNS: Cerebral ischemia manifested by unconsciousness, seizures paralysis, confusion, numbness of the hands. Headache, dizziness, weakness, drowsiness, lightheadedness, somnolence, lethargy, euphoria, weakness of short duration, apprehension, anxiety, malaise, blurred vision. Respiratory: Tightness in chest, cough, dyspnea, sensation of choking. GI: N&V;, diarrhea, anorexia, parotid swelling, change in sense of taste, salivation, dry mouth, ileus, constipation, acute pancreatitis (rare). Other: Hyperglycemia (may be serious enough to require treatment), sweating, flushing, sensation of warmth, transient neurologic findings due to alteration in regional blood flow to the brain, hyperosmolar coma in infants, tinnitus, hearing loss, retention of nitrogenous wastes, acute pancreatitis, back pain, increased nocturia, lacrimation, hypersensitivity reactions, papilledema, hirsutism, decreased libido. Pain, cellulitis without sloughing, warmth or pain along injected vein, phlebitis at injection site, extravasation.

Laboratory Test Alterations: False + or uric acid.

Overdose Management: Symptoms: Hypotension, excessive hyperglycemia. Treatment: Use the Trendelenburg maneuver to reverse hypotension.

Drug Interactions: Anticoagulants, oral / Anticoagulant effect R/T plasma protein binding Nitrites / Hypotensive effect Phenytoin / Anticonvulsant effect of phenytoin Reserpine / Hypotensive effect Sulfonylureas / Destablization of the client hyperglycemia Thiazide diuretics / Hyperglycemic, hyperuricemic, and antihypertensive diazoxide effect Vasodilators, peripheral / Hypotensive effect

How Supplied: Injection: 15 mg/mL

Dosage
?IV Push (30 sec or less) Hypertensive crisis.
Adults: 1-3 mg/kg up to a maximum of 150 mg; may be repeated at 5-15-min intervals until adequate BP response obtained. Drug may then be repeated at 4-24-hr intervals for 4-5 days or until oral antihypertensive therapy can be initiated. Pediatric: 1-3 mg/kg (30-90 mg/m ²) using the same dosing intervals as adults.
Repeated use can result in sodium and water retention; therefore, a diuretic may be needed to avoid CHF and for maximum reduction of BP.