FLUMAZENIL

FLUMAZENIL (flu-ma'ze-nil) Mazicon , Romazicon Classifications: benzodiazepine antagonist; Therapeutic: benzodiazepine antidote Pregnancy Category: C

Availability

0.1 mg/mL injection

Action

Antagonizes the effects of benzodiazepine on the CNS, including sedation, impairment of recall, and psychomotor impairment. Does not reverse the effects of opioids.

Therapeutic Effect

Reverses the action of a benzodiazepine.

Uses

Reversal of sedation induced by benzodiazepine for anesthesia or diagnostic or therapeutic procedures and through overdose.

Unlabeled Uses

Seizure disorders, alcohol intoxication, hepatic encephalopathy, facilitation of weaning from mechanical ventilation.

Contraindications

Hypersensitivity to flumazenil or to benzodiazepines; patients given a benzodiazepine for control of a life-threatening condition; patients showing signs of cyclic antidepressant overdose; seizure-prone individuals; during labor and delivery; pregnancy (category C); children <18 y.

Cautious Use

Hepatic function impairment, older adults, lactation, intensive care patients, head injury, anxiety or pain disorder; drug- and alcohol-dependent patients, and physical dependence upon benzodiazepines.

Route & Dosage

Reversal of Sedation Adult: IV 0.2 mg over 15 sec, may repeat 0.2 mg each min for 4 additional doses or a cumulative dose of 1 mg Benzodiazepine Overdose Adult: IV 0.2 mg over 30 sec, if no response after 30 sec, then 0.3 mg over 30 sec, may repeat with 0.5 mg each min (max: cumulative dose of 3 mg)

Administration

Intravenous PREPARE: Direct: May give undiluted or diluted. If diluted use D5W, Lactated Ringer's, NS.   ADMINISTER: Direct for Reversal of Anesthesia: • Ensure patency of IV before administration of flumazenil, since extravasation will cause local irritation.• Do not give as bolus dose. Give through an IV that is freely flowing into a large vein.  Direct for Reversal of Anesthesia or Sedation: Give each dose slowly over 15 sec. In high-risk patients, slow the rate to provide the smallest effective dose.  Direct for Benzodiapine Overdose: • Give each dose in small quantities over 30 sec.• Use all diluted solutions within 24 h of dilution.

Adverse Effects (≥1%)

CNS: Emotional lability, headache, dizziness, agitation, resedation, seizures, blurred vision. GI: Nausea, vomiting, hiccups. Other: Shivering, pain at injection site, hypoventilation.

Interactions

Drug: May antagonize effects of zaleplon, zolpidem; may cause convulsions or arrhythmias with tricyclic antidepressants.

Pharmacokinetics

Onset: 1–5 min. Peak: 6–10 min. Duration: 2–4 h. Metabolism: In the liver to inactive metabolites. Elimination: 90–95% in urine, 5–10% in feces within 72 h. Half-Life: 54 min.

Nursing Implications

Assessment & Drug Effects

• Monitor respiratory status carefully until risk of resedation is unlikely (up to 120 min). Drug may not fully reverse benzodiazepine-induced ventilatory insufficiency.
• Monitor carefully for seizures and take appropriate precautions.

Patient & Family Education

• Do not drive or engage in potentially hazardous activities until at least 18–24 h after discharge following a procedure.
• Do not ingest alcohol or nonprescription drugs for 18–24 h after flumazenil is administered or if the effects of the benzodiazepine persist.

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Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug