General

Vasopressin should be used cautiously in the presence of epilepsy, migraine, asthma, heart failure or any state in which a rapid addition to extracellular water may produce hazard for an already overburdened system.

Chronic nephritis with nitrogen retention contraindicates the use of vasopressin until reasonable nitrogen blood levels have been attained.

Information for Patients

Side effects such as blanching of skin, abdominal cramps, and nausea may be reduced by taking 1 or 2 glasses of water at the time of vasopressin administration.  These side effects are usually not serious and probably will disappear within a few minutes.

Laboratory Tests

Electrocardiograms (ECG) and fluid and electrolyte status determinations are recommended at periodic intervals during therapy.

Drug Interactions

The following drugs may potentiate the antidiuretic effect of vasopressin when used concurrently: carbamazepine; chlorpropamide; clofibrate; urea; fludrocortisone; tricyclic antidepressants.

The following drugs may decrease the antidiuretic effect of vasopressin when used concurrently: demeclocycline; norepinephrine; lithium; heparin; alcohol.

Ganglionic blocking agents may produce a marked increase in sensitivity to the pressor effects of vasopressin.

Pregnancy Category C

Animal reproduction studies have not been conducted with vasopressin.  It is also not known whether vasopressin can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity.  Vasopressin should be given to a pregnant woman only if clearly needed.

Labor and Delivery

Doses of vasopressin sufficient for an antidiuretic effect are not likely to produce tonic uterine contractions that could be deleterious to the fetus or threaten the continuation of the pregnancy.

Nursing Mothers

Caution should be exercised when vasopressin is administered to a nursing woman.

Body as a Whole

Anaphylaxis (cardiac arrest and/or shock) has been observed shortly after injection of vasopressin.

Cardiovascular

Cardiac arrest, circumoral pallor, arrhythmias, decreased cardiac output, angina, myocardial ischemia, peripheral vasoconstriction, and gangrene.

Gastrointestinal

Abdominal cramps, nausea, vomiting, passage of gas.

Nervous System

Tremor, vertigo, ‘‘pounding’’ in head.

Respiratory

Bronchial constriction.

Skin and Appendages

Sweating, urticaria, cutaneous gangrene.

Overdosage

Water intoxication may be treated with water restriction and temporary withdrawal of vasopressin until polyuria occurs. Severe water intoxication may require osmotic diuresis with mannitol, hypertonic dextrose, or urea alone or with furosemide.

Abdominal Distention

In the average postoperative adult patient, give 5 units (0.25 mL) initially, increase to 10 units (0.5 mL) at subsequent injections if necessary.  It is recommended that Vasopressin Injection be given IM and that injections be repeated at three or four hour intervals as required.  Dosage to be reduced proportionately for pediatric patients.

Vasopressin Injection used in this manner will frequently prevent, or relieve, postoperative distention.  These recommendations apply also to distention complicating pneumonia or other acute toxemias.

Abdominal Roentgenography

For the average case, two injections of 10 units (0.5 mL) each are suggested.  These should be given two hours and one-half hour, respectively, before films are exposed.  Many roentgenologists advise giving an enema prior to the first dose of Vasopressin Injection.

Diabetes Insipidus

Vasopressin Injection may be given by injection or administered intranasally on cotton pledgets, by nasal spray, or by dropper.  The dose by injection is 5 to 10 units (0.25 to 0.5 mL) repeated two or three times daily as needed.  When Vasopressin Injection is administered intranasally by spray or on pledgets, the dosage and interval between treatments must be determined for each patient.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.