Last reviewed 2026-04-20 · How we verify

Inapsine (DROPERIDOL)

Inapsine (Droperidol) is a dopamine-2 receptor antagonist, a small molecule drug class, originally developed by AKORN INC and currently owned by Rising. It targets the D(2) dopamine receptor to treat Intra-Operative Nausea and Vomiting and Post-Operative Nausea and Vomiting. Inapsine is off-patent with 10 generic manufacturers, and its half-life is approximately 1.9 hours with 75% bioavailability. The drug has been FDA-approved since 1970. Key safety considerations include its potential for QT interval prolongation.

At a glance

Approved indications

• Intra-Operative Nausea and Vomiting
• Post-Operative Nausea and Vomiting

Boxed warnings

• WARNING Cases of QT prolongation and/or torsade de pointes have been reported in patients receiving droperidol at doses at or below recommended doses. Some cases have occurred in patients with no known risk factors for QT prolongation and some cases have been fatal. Due to its potential for serious proarrhythmic effects and death, droperidol should be reserved for use in the treatment of patients who fail to show an acceptable response to other adequate treatments, either because of insufficient effectiveness or the inability to achieve an effective dose due to intolerable adverse effects from those drugs (see CONTRAINDICATIONS , WARNINGS , PRECAUTIONS , and ADVERSE REACTIONS ). Cases of QT prolongation and serious arrhythmias (e.g., torsade de pointes) have been reported in patients treated with droperidol. Based on these reports, all patients should undergo a 12-lead ECG prior to administration of droperidol to determine if a prolonged QT interval (i.e., QTc greater than 440 msec for males or 450 msec for females) is present. If there is a prolonged QT interval, droperidol should NOT be administered. For patients in whom the potential benefit of droperidol treatment is felt to outweigh the risks of potentially serious arrhythmias, ECG monitoring should be performed prior to treatment and continued for 2-3 hours after completing treatment to monitor for arrhythmias. Droperidol is contraindicated in patients with known or suspected QT prolongation, including patients with congenital long QT syndrome. Droperidol should be administered with extreme caution to patients who may be at risk for development of prolonged QT syndrome (e.g., congestive heart failure, bradycardia, use of a diuretic, cardiac hypertrophy, hypokalemia, hypomagnesemia, or administration of other drugs known to increase the QT interval). Other risk factors may include age over 65 years, alcohol abuse, and use of agents such as benzodiazepines, volatile anesthetics, and IV opiates. Droperidol should be initiated at a low dose and adjusted upward, with caution, as needed to achieve the desired effect.

Common side effects

• Hypotension
• Tachycardia
• Dysphoria
• Postoperative drowsiness
• Restlessness
• Hyperactivity
• Anxiety
• Dystonia
• Akathisia
• Oculogyric crisis
• Anaphylaxis
• Dizziness

Drug interactions

• High Risk QT Prolonging Agents
• cabergoline
• entacapone
• levodopa
• pergolide
• pramipexole
• ropinirole
• ziprasidone

Key clinical trials

• TEAS Combined With Triple Antiemetic Drugs to Prevent PONV in High-Risk Patients (NA)
• Akathisia in Post Operative Outpatients Surgery (PHASE3)
• E7 TCR T Cells for Human Papillomavirus-Associated Cancers (PHASE1,PHASE2)
• Postoperative Vomiting in Children: Comparison Tri - Versus bi -Prophylaxis (NA)
• Assessment of Drug Liking In Peri-procedural Clinical Settings (EARLY_PHASE1)
• Supra Inguinal Fascia Iliaca Block as Rescue Analgesia Following Total Hip Arthroplasty (NA)
• Haloperidol, Droperidol, Ondansetron in Cannabis Hyperemesis (PHASE3)
• Opioid Free Anesthesia-Analgesia Strategy and Surgical Stress in Elective Open Abdominal Aortic Aneurysm Repair (PHASE4)

Primary sources

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