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Inapsine Side Effects

Generic Name: droperidol

Note: This page contains information about the side effects of droperidol. Some of the dosage forms included on this document may not apply to the brand name Inapsine.

For the Consumer

Applies to droperidol: injection injectable, injection solution

In addition to its needed effects, some unwanted effects may be caused by droperidol (the active ingredient contained in Inapsine). In the event that any of these side effects do occur, they may require medical attention.

If any of the following side effects occur while taking droperidol, check with your doctor or nurse immediately:

More common:
  • Blurred vision
  • confusion
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • sweating
  • unusual tiredness or weakness
Less common:
  • Chills
  • cough
  • difficulty with breathing
  • difficulty with swallowing
  • dizziness
  • fast heartbeat
  • noisy breathing
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • skin rash, hives, or itching
  • tightness in the chest
Incidence not known:
  • Chest pain or discomfort
  • fainting
  • fast, pounding, or irregular heartbeat or pulse
  • irregular or slow heart rate
  • low blood pressure or pulse
  • severe confusion or loss of consciousness

Minor Side Effects

Some of the side effects that can occur with droperidol may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common:
  • Anxiety
  • drowsiness
  • restlessness
  • trouble sitting still
Incidence not known:
  • Difficulty with speaking
  • drooling
  • loss of balance control
  • muscle trembling, jerking, or stiffness
  • seeing, hearing, or feeling things that are not there
  • shuffling walk
  • stiffness of the limbs
  • twisting movements of the body
  • uncontrolled movements, especially of the face, neck, and back

For Healthcare Professionals

Applies to droperidol: compounding powder, injectable solution


Frequency not reported: Hypotension, irregular cardiac rhythm, mild or moderate tachycardia, QT prolongation, serious arrhythmias (e.g., torsades de pointes), ventricular tachycardia, cardiac arrest, death (some of these side effects occurred in patients with no known risk factors, and some were associated with droperidol (the active ingredient contained in Inapsine) doses at or below recommended doses)[Ref]

Nervous system

Unexplained fever, alteration of consciousness, extrapyramidal dysfunction, autonomic instability and elevated creatine kinase are all symptoms associated with neuroleptic agents. If these symptoms develop in patients receiving droperidol (the active ingredient contained in Inapsine) therapy, immediate discontinuation of the drug is warranted.

Extrapyramidal symptoms such as acute dystonia, parkinsonism, akathisia, and oculogyric crisis have been reported in patients receiving droperidol in doses as low as 0.65 mg. In addition, cases of akathisia have been reported in patients during epidural anesthesia.[Ref]

Frequency not reported: Dysphoria, drowsiness, restlessness, hyperactivity, anxiety, hallucinations, dizziness, extrapyramidal symptoms, neuroleptic malignant syndrome, confusion, nervousness, paresthesia, somnolence, tremor, akathisia, oculogyric crisis, unexplained fever, alteration of consciousness, autonomic instability[Ref]


Frequency not reported: pharyngitis, rhinitis, bronchospasm, laryngospasm (reported as rare)[Ref]


Frequency not reported: Anaphylaxis (uncommon)[Ref]


Frequency not reported : Injection site pain[Ref]


Frequency not reported: Chills and/or shivering, tongue-swelling, sweating[Ref]


1. "Product Information. Droperidol (droperidol)." Abbott Pharmaceutical, Abbott Park, IL.

2. "Product Information. Inapsine (droperidol)." Janssen Pharmaceutica, Titusville, NJ.

3. Vice President, Medical Affairs and Worldwide Drug Safety "Important drug warning letter. Available from: URL:" ([2001 Dec 4]):

4. Miyai N, Kawasaki T, Sugihara H, Kayo R "Coronary artery spasm as a cause of droperidol-induced ventricular fibrillation." Anesth Analg 103 (2006): 1602-3

5. Merridew GC, Keefe PA "Presence of extrapyramidal side-effects from droperidol in low dose." Anaesth Intensive Care 22 (1994): 319-20

6. Athanassiadis C, Karamanis A "Akathisia after long-term epidural use of droperidol: a case report." Pain 50 (1992): 203-4

7. Arrowsmith J, Gams RA "Dystonia with droperidol therapy." N Engl J Med 305 (1981): 227

8. Szuba MP, Bergman KS, Baxter LR Jr, Guze BH, Reynolds CA, Pelletier LR "Safety and efficacy of high-dose droperidol in agitated patients." J Clin Psychopharmacol 12 (1992): 144-6

9. Foster PN, Stickle BR, Laurence AS "Akathisia following low-dose droperidol for antiemesis in day-case patients." Anaesthesia 51 (1996): 491-4

10. Patton CM Jr. "Rapid induction of acute dyskinesia by droperidol." Anesthesiology 43 (1975): 126-7

11. Patel P, Bristow G "Postoperative neuroleptic malignant syndrome. A case report." Can J Anaesth 34 (1987): 515-8

12. Ward NG "Akathisia associated with droperidol during epidural anesthesia." Anesthesiology 71 (1989): 786-7

13. Ratan DA, Smith AH "Neuroleptic malignant syndrome secondary to droperidol." Biol Psychiatry 34 (1993): 421-2

14. Chambers RA, Druss BG "Droperidol: Efficacy and side effects in psychiatric emergencies." J Clin Psychiatry 60 (1999): 664-7

15. Bamrah JS "Neuroleptic-induced pyrexia. A benign variant." J Nerv Ment Dis 176 (1988): 741-3

16. Silberstein SD, Young WB, Mendizabal JE, Rothrock JF, Alam AS "Acute migraine treatment with droperidol: A randomized, double-blind, placebo-controlled trial." Neurology 60 (2003): 315-21

17. Melnick BM "Extrapyramidal reactions to low-dose droperidol." Anesthesiology 69 (1988): 424-6

18. Holmes VF, Adams F, Fernandez F "Respiratory dyskinesia due to antiemetic therapy in a cancer patient." Cancer Treat Rep 71 (1987): 415-6

19. Clark RJ "Tongue-swelling with droperidol." Anaesth Intensive Care 21 (1993): 898

Not all side effects for Inapsine may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.