Flumazenil Side Effects
Medically reviewed by Drugs.com. Last updated on Jul 22, 2020.
Commonly reported side effects of flumazenil include: dizziness, nausea, and vomiting. Other side effects include: headache, agitation, depersonalization, depression, dysphoria, dyspnea, euphoria, hyperventilation, insomnia, nervousness, palpitations, paranoid ideation, paresthesia, tremor, uncontrolled crying, visual disturbance, diaphoresis, pain at injection site, and xerostomia. See below for a comprehensive list of adverse effects.
For the Consumer
Applies to flumazenil: parenteral injection
Side effects include:
For Healthcare Professionals
Applies to flumazenil: intravenous solution
Very common (10% or more): Dizziness (vertigo, ataxia) (10%)
Common (1% to 10%): Headache, paresthesia (sensation abnormal, hypoesthesia)
Frequency not reported: Convulsions, somnolence, speech disorder (dysphonia, thick tongue)[Ref]
Convulsions have occurred in patients with severe hepatic impairment, inpatients relying on benzodiazepine effects to control seizures, patients physically dependent on benzodiazepines, and those who have ingested large doses of other drugs (mixed-drug overdose).[Ref]
Common (1% to 10%): Agitation (anxiety, nervousness, dry mouth, tremor, palpitations, insomnia, dyspnea, hyperventilation), emotional lability (crying abnormal, depersonalization, euphoria, increased tears, depression, dysphoria, paranoia)
Frequency not reported: Confusion (difficulty concentrating, delirium)
Common (1% to 10%): Cutaneous vasodilation (sweating, flushing, hot flushes)
The majority of deaths occurred in patients with serious underlying disease or in patients who had injects large amounts of non-benzodiazepine drugs (usually cyclic antidepressants) as part of an overdose.
Common (1% to 10%): Fatigue (asthenia, malaise)
Frequency not reported: Death, abnormal hearing (transient hearing impairment, hyperacusis, tinnitus), rigors, shivering
Postmarketing reports: Withdrawal symptoms[Ref]
Common (1% to 10%): Injection site pain, injection site reaction (thrombophlebitis, skin abnormality, rash)[Ref]
Common (1% to 10%): Abnormal vision (visual field defect, diplopia)[Ref]
Frequency not reported: Hiccup[Ref]
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11. Griffiths RR, Evans SM, Guarino JJ, Roache JD, Furman WR, Liebson I, Schwam EM "Intravenous flumazenil following acute and repeated exposure to lorazepam in healthy volunteers: antagonism and precipitated withdrawal." J Pharmacol Exp Ther 265 (1993): 1163-74
12. Seebach J, Jost R "Flumazenil-induced psychotic disorder in hepatic encephalopathy." Lancet 339 (1992): 488-9
13. Short TG, Maling T, Galletly DC "Ventricular arrhythmia precipitated by flumazenil." Br Med J (Clin Res Ed) 296 (1988): 1070-1
14. Birch BR "Cardiac arrest associated with flumazenil." BMJ 305 (1992): 180-1
15. Katz Y, Boulos M, Singer P, Rosenberg B "Cardiac arrest associated with flumazenil." BMJ 304 (1992): 1415
16. Herd B, Clarke F "Complete heart block after flumazenil." Hum Exp Toxicol 10 (1991): 289
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18. Lopez A, Rebollo J "Benzodiazepine withdrawal syndrome after a benzodiazepine antagonist." Crit Care Med 18 (1990): 1480-1
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Some side effects may not be reported. You may report them to the FDA.