droperidol
Inapsine

Available forms
Available by prescription only
Injection: 2.5 mg/ml

Indications and dosages
 Delirium. Adults: 5 mg I.M., p.r.n. It’s given for its quick onset and sedative quality.
 Anesthetic premedication. Adults: 2.5 to 10 mg I.M. 30 to 60 minutes before induction of general anesthesia.
Children ages 2 to 12: 0.088 to 0.165 mg/kg I.V. or I.M.
 Adjunct for induction of general anesthesia. Adults: 0.22 to 0.275 mg/kg I.V. (preferably) or I.M. with an analgesic or general anesthetic.
Children: 0.088 to 0.165 mg/kg I.V. or I.M.
 Adjunct for maintenance of general anesthesia. Adults: 1.25 to 2.5 mg I.V.
 For use without general anesthetic during diagnostic procedures. Adults: 2.5 to 10 mg I.M. 30 to 60 minutes before procedure. Additional doses of 1.25 to 2.5 mg I.V. are given, p.r.n.
 Adjunct to regional anesthesia. Adults: 2.5 to 5 mg I.M. or slow I.V. injection.
 Antiemetic in conjunction with chemotherapy ◇. Adults: 0.5 to 2 mg I.V. or I.M. before chemotherapy and then q 3 to 4 hours, p.r.n.

Pharmacodynamics
Tranquilizer action: Droperidol produces marked sedation by directly blocking subcortical receptors. It also blocks CNS receptors at the chemoreceptor trigger zone, producing an antiemetic effect. Droperidol also causes mild alpha-adrenergic blockade and peripheral vascular dilation, and reduces pressor effects of epinephrine.

Pharmacokinetics
Absorption: Well absorbed after I.M. injection.
Distribution: Not well understood. Drug crosses the blood-brain barrier and is distributed in the CSF. It also crosses the placental barrier.
Metabolism: Metabolized by the liver to p-fluorophenylacetic acid and p-hydroxypiperidine.
Excretion: Excreted in urine and feces.

Contraindications and precautions
Contraindicated in patients hypersensitive to or intolerant of drug. Contraindicated in patients with known or suspected QT prolongation, including patients with congenital long QT syndrome.
  Use cautiously in patients with hypotension and other CV disease because of its vasodilatory effects, in patients with hepatic or renal disease for whom drug clearance may be impaired, and in patients taking other CNS depressants, including alcohol, opiates, and sedatives, because droperidol may potentiate the effects of these drugs. Also use cautiously in those at risk for developing QT prolongation syndrome (those with congestive heart failure, bradycardia, cardiac hypertrophy, hypokalemia, hypomagnesemia, or those using a diuretic or other drug that causes QT prolongation).

Interactions
Drug-drug. Epinephrine: May paradoxically enhance hypotensive effects. Don’t use together.
Fentanyl citrate: May cause hypertension and respiratory depression. Avoid use together if possible.
Opiates; other analgesics; other CNS depressants, such as barbiturates, sedative-hypnotics, and tranquilizers: Causes additive CNS depression and pharmacologic effects. Reduce dosage of both drugs.
Drug-lifestyle. Alcohol use: Potentiates CNS depressant effects. Discourage alcohol use.

Adverse reactions
CNS: sedation, altered consciousness, dysphoria, drowsiness, postoperative hallucinations, extrapyramidal reactions, temporarily altered EEG pattern.
CV: hypotension with rebound tachycardia, bradycardia, decreased pulmonary artery pressure, QT prolongation.
Respiratory: respiratory depression.
Other: anaphylaxis, chills.

Effects on lab test results
None reported.

Overdose and treatment
Signs and symptoms of overdose include extensions of the pharmacologic actions of drug.
 Treat symptomatically and supportively.

Special considerations
 ALERT Discontinue drug if patient shows signs of hypersensitivity, severe persistent hypotension, respiratory depression, paradoxical hypertension, or dystonia.
• Have fluids and other measures to manage hypotension readily available.
• Droperidol has been used for its antiemetic effects in preventing or treating chemotherapy-induced nausea and vomiting, especially that produced by cisplatin.
• Monitor vital signs and observe patient for extrapyramidal reactions. Droperidol is related to haloperidol and is more likely than other antipsychotic drugs to cause extrapyramidal symptoms.
• Observe patient for postoperative hallucinations or emergence delirium and drowsiness. Some alteration of consciousness may persist for 12 hours.
Breast-feeding patients
• It isn’t known whether droperidol appears in breast milk.
Pediatric patients
• Safety and efficacy in children younger than age 2 haven’t been established.
Geriatric patients
• Use drug cautiously. Elderly patients are more prone to extrapyramidal reactions, CNS disturbances, and CV adverse effects.

Patient education
• Advise patient of possible postoperative effects.
• Warn patient to rise slowly to prevent orthostatic hypotension.

Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE THREATENING.
◆ Canada only
◇ Unlabeled clinical use