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Quick facts
- Drug class
- Benzodiazepine Antagonist [EPC]
- How it is given
- intravenous
- Type
- human prescription drug
- RxNorm ID
- 204508
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
INDICATIONS AND USAGE Adult Patients Flumazenil Injection, USP is indicated for the complete or partial reversal of the sedative effects of benzodiazepines in cases where general anesthesia has been induced and/or maintained with benzodiazepines, where sedation has been produced with benzodiazepines for diagnostic and therapeutic procedures, and for the management of benzodiazepine overdose. Pediatric Patients (aged 1 to 17) Flumazenil Injection, USP is indicated for the reversal of conscious sedation induced with benzodiazepines (see PRECAUTIONS: Pediatric Use ).
About this medicine
DESCRIPTION Flumazenil Injection, USP is a benzodiazepine receptor antagonist. Chemically, flumazenil is ethyl 8-fluoro-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a](1,4) benzodiazepine-3-carboxylate. Flumazenil has an imidazobenzodiazepine structure, a calculated molecular weight of 303.3, and the following structural formula: Flumazenil is a white to off-white crystalline compound with an octanol: buffer partition coefficient of 14 to 1 at pH 7.4. It is insoluble in water but slightly soluble in acidic aqueous solutions. Flumazenil injection is available as a sterile parenteral dosage form for intravenous administration. Each mL contains 0.1 mg of flumazenil compounded with 1.8 mg of methylparaben, 0.2 mg of propylparaben, 0.9% sodium chloride, 0.01% edetate disodium, and 0.01% acetic acid; the pH is adjusted to approximately 4 with hydrochloric acid and/or, if necessary, sodium hydroxide. Structural Formula
Who should not take it
CONTRAINDICATIONS Flumazenil is contraindicated: in patients with a known hypersensitivity to flumazenil or benzodiazepines. in patients who have been given a benzodiazepine for control of a potentially life-threatening condition (e.g., control of intracranial pressure or status epilepticus). in patients who are showing signs of serious cyclic antidepressant overdose (see WARNINGS ).
Warnings
WARNINGS THE USE OF FLUMAZENIL HAS BEEN ASSOCIATED WITH THE OCCURRENCE OF SEIZURES. THESE ARE MOST FREQUENT IN PATIENTS WHO HAVE BEEN ON BENZODIAZEPINES FOR LONG-TERM SEDATION OR IN OVERDOSE CASES WHERE PATIENTS ARE SHOWING SIGNS OF SERIOUS CYCLIC ANTIDEPRESSANT OVERDOSE. PRACTITIONERS SHOULD INDIVIDUALIZE THE DOSAGE OF FLUMAZENIL AND BE PREPARED TO MANAGE SEIZURES. Risk of Seizures The reversal of benzodiazepine effects may be associated with the onset of seizures in certain high-risk populations. Possible risk factors for seizures include: concurrent major sedative-hypnotic drug withdrawal, recent therapy with repeated doses of parenteral benzodiazepines, myoclonic jerking or seizure activity prior to flumazenil administration in overdose cases, or concurrent cyclic antidepressant poisoning. Flumazenil is not recommended in cases of serious cyclic antidepressant poisoning, as manifested by motor abnormalities (twitching, rigidity, focal seizure), dysrhythmia (wide QRS, ventricular dysrhythmia, heart block), anticholinergic signs (mydriasis, dry mucosa, hypoperistalsis), and cardiovascular collapse at presentation. In such cases flumazenil should be withheld and the patient should be allowed to remain sedated (with ventilatory and circulatory support as needed) until the signs of antidepressant toxicity have subsided. Treatment with flumazenil has no known benefit to the seriously ill mixed-overdose patient other than reversing sedation and should not be used in cases where seizures (from any cause) are likely. Most convulsions associated with flumazenil administration require treatment and have been successfully managed with benzodiazepines, phenytoin or barbiturates. Because of the presence of flumazenil, higher than usual doses of benzodiazepines may be required. Hypoventilation Patients who have received flumazenil for the reversal of benzodiazepine effects (after conscious sedation or general anesthesia) should be monitored for resedation, respiratory depression, or other residual benzodiazepine effects for an appropriate period (up to 120 minutes) based on the dose and duration of effect of the benzodiazepine employed. […]
Reported side effects
ADVERSE REACTIONS Serious Adverse Reactions Deaths have occurred in patients who received flumazenil in a variety of clinical settings. The majority of deaths occurred in patients with serious underlying disease or in patients who had ingested large amounts of non-benzodiazepine drugs (usually cyclic antidepressants), as part of an overdose. Serious adverse events have occurred in all clinical settings, and convulsions are the most common serious adverse events reported. Flumazenil administration has been associated with the onset of convulsions in patients with severe hepatic impairment and in patients who are relying on benzodiazepine effects to control seizures, are physically dependent on benzodiazepines, or who have ingested large doses of other drugs (mixed-drug overdose) (see WARNINGS ). Two of the 446 patients who received flumazenil in controlled clinical trials for the management of a benzodiazepine overdose had cardiac dysrhythmias (1 ventricular tachycardia,1 junctional tachycardia). Adverse Events in Clinical Studies The following adverse reactions were considered to be related to flumazenil administration (both alone and for the reversal of benzodiazepine effects) and were reported in studies involving 1875 individuals who received flumazenil in controlled trials. Adverse events most frequently associated with flumazenil alone were limited to dizziness, injection site pain, increased sweating, headache, and abnormal or blurred vision (3% to 9%). […]
Interactions with other medicines
Drug Interactions Interaction with central nervous system depressants other than benzodiazepines has not been specifically studied; however, no deleterious interactions were seen when flumazenil was administered after narcotics, inhalational anesthetics, muscle relaxants and muscle relaxant antagonists administered in conjunction with sedation or anesthesia. Particular caution is necessary when using flumazenil in cases of mixed drug overdosage since the toxic effects (such as convulsions and cardiac dysrhythmias) of other drugs taken in overdose (especially cyclic antidepressants) may emerge with the reversal of the benzodiazepine effect by flumazenil (see WARNINGS ). The use of flumazenil is not recommended in epileptic patients who have been receiving benzodiazepine treatment for a prolonged period. Although flumazenil exerts a slight intrinsic anticonvulsant effect, its abrupt suppression of the protective effect of a benzodiazepine agonist can give rise to convulsions in epileptic patients. Flumazenil blocks the central effects of benzodiazepines by competitive interaction at the receptor level. The effects of nonbenzodiazepine agonists at benzodiazepine receptors, such as zopiclone, triazolopyridazines and others, are also blocked by flumazenil. The pharmacokinetics of benzodiazepines are unaltered in the presence of flumazenil and vice versa. There is no pharmacokinetic interaction between ethanol and flumazenil.
If too much is taken
OVERDOSAGE There is limited experience of acute overdosage with flumazenil. There is no specific antidote for overdose with flumazenil. Treatment of an overdose with flumazenil injection should consist of general supportive measures including monitoring of vital signs and observation of the clinical status of the patient. Intravenous bolus administration of doses ranging from 2.5 to 100 mg (exceeding those recommended) of flumazenil, when administered to healthy normal volunteers in the absence of a benzodiazepine agonist, produced no serious adverse reactions, severe signs or symptoms, or clinically significant laboratory test abnormalities. In clinical studies, most adverse reactions to flumazenil were an extension of the pharmacologic effects of the drug in reversing benzodiazepine effects. Reversal with an excessively high dose of flumazenil injection may produce anxiety, agitation, increased muscle tone, hyperesthesia and possibly convulsions. Convulsions have been treated with barbiturates, benzodiazepines and phenytoin, generally with prompt resolution of the seizures (see WARNINGS ).
Storing it safely
STORAGE Store at 25ºC (77ºF); excursions permitted to 15º to 30ºC (59º to 86ºF) [See USP Controlled Room Temperature]. Manufactured by: HIKMA FARMACÊUTICA (PORTUGAL), S.A.. Estrada do Rio da Mó, nº 8, 8A e 8B - Fervença - 2705 – 906 Terrugem SNT, PORTUGAL Distributed by: Hikma Pharmaceutical USA Inc . Berkeley Heights, NJ 07922 Revised: July 2020 PIN216-WES/4
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This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 14 June 2024. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.