Vasopressin (8-Arginine-Vasopressin)

A to Z Drug Facts

 Action Promotes resorption of water through kidney. At high doses, stimulates contraction of smooth muscle causing vasoconstriction, increased peristaltic activity, and gall-bladder contractions.

 Indications Treatment of neurogenic diabetes insipidus; prevention and treatment of postoperative abdominal distention; facilitation of abdominal roentgenography.

Treatment of bleeding esophageal varices.

 Contraindications Standard considerations.

 Route/Dosage

Diabetes Insipidus

ADULTS & CHILDREN: IM/SC 2.5 to 10 units 2 to 4 times daily as needed.

Abdominal Distention

ADULTS: IM 5 units initially; subsequent injections q 3 to 4 hr prn. May increase the dose to 10 units if necessary.

Abdominal Roentgenography

ADULTS: IM/SC 2 injections of 10 units each administered 2 hr and 30 min before films are exposed.

Bleeding Esophageal Varices

ADULTS: IV Infuse initially at 0.2 to 0.4 U/min and increase to 0.9 U/min if necessary.

 Interactions

Carbamazepine, chlorpropamide: May potentiate antidiuretic effect of vasopressin.

 Lab Test Interferences None well documented.

 Adverse Reactions

CV: ANGINA. GI: Abdominal cramps; nausea; vomiting; gas. OTHER: Gangrene; ischemic colitis; tissue necrosis (with extravasation); allergic reaction (cardiac arrest, tremor, vertigo, sweating).

 Precautions

Pregnancy: Category C. Lactation: Undetermined. Special risk patients: Use drug with caution in patients with epilepsy, migraine, asthma, heart failure, or any condition where a rapid rise in extracellular water may result in further compromise. Chronic nephritis with nitrogen retention: Contraindicates use until reasonable nitrogen blood levels have been attained. Extravasation: Severe vasoconstriction and local tissue necrosis may result if drug extravasates during IV infusion. Hypersensitivity: Local or systemic reactions, including anaphylaxis, may occur. Vascular disease: Use extreme caution in patients with vascular disease. Water intoxication: May occur. Early signs include confusion, drowsiness, listlessness, and headache.

 Administration/Storage

• Store at room temperature. Do not freeze.
• Give 1 to 2 glasses of water with dose to prevent skin blanching, abdominal cramps, and nausea.
• If administering via IV infusion, 0.9% Normal Saline or D5W to a concentration of 0.1 to 1 U/ml. Insure patency of venous access and use infusion control device.

 Assessment/Interventions

• Obtain patient history, including drug history and any known allergies.
• Monitor for allergic reactions, including tremor, sweating, vertigo, circumoral pallor, “pounding in head,” abdominal cramps, flatus, nausea, vomiting, urticaria, bronchial constriction.
• Monitor I & O, and weigh daily.
• Monitor urine specific gravity and osmolarity.
• Monitor vital signs.
• Monitor ECG and fluid and electrolyte status at frequent intervals during prolonged therapy.
• Monitor patient for evidence of water intoxication (confusion, drowsiness, listlessness, headache). Report to health care provider immediately if noted.
• Monitor for therapeutic response: Decreased urine output;decreased thirst.
• Assess reduction of thirst.
• In abdominal distention, assess bowel sounds and presence or absence of flatus.

 Patient/Family Education

• Tell patient to take with 1 to 2 glasses of water to prevent skin blanching, nausea, abdominal cramping.
• Caution patient to withhold medication and to notify health care provider of chest pain.
• Tell patient to report drowsiness, listlessness, and headache to health care provider and to restrict water intake.
• Explain that urine output should decrease after use.
• Tell patient to monitor weight daily.
• Instruct patient to avoid alcohol intake during therapy.
• Remind patients with diabetes insipidus to carry appropriate medical identification.

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Copyright © 2003 Facts and Comparisons
David S. Tatro
A to Z Drug Facts