Flumazenil

From Anvita Health Wiki

Contents 1 Introduction 2 Indications 3 Contraindications 4 Pharmacokinetics 5 Adverse-effects 6 Drug-interactions 7 Mechanism-of-action 8 More General Terms 9 Additional Terms 10 Internet Database 11 References

Introduction

• Tradenames: Mazicon, Romazicon.

Indications

• benzodiazepine sedation reversal:

• 0.2 mg IV over 15 sec, then 0.2 mg every 1 min PRN
• up to 1 mg.

• benzodiazepine overdose reversal:

• 0.2 mg IV over 30 sec, then 0.3-0.5 mg every 30 sec PRN
• up to 3 mg.

• * Note: 1/2 life 40-80 minutes is considerably less than that of most benzodiazepines

Contraindications

• patients with serious signs of tricyclic antidepressant overdose
• patients given benzodiazepines for control of potentially life-threatening conditions

• status epilepticus
• control of intracranial pressure
  

• pregnancy category = c
• safety in lactation = ?

Pharmacokinetics

• rapidly inactivated by the liver by hydroxylation
• 1/2life is 1 hour
• reversal of benzodiazepine may take effect in 1-3 minutes & last 1-5 hours
  

• elimination via liver
• elimination via kidney
• 1/2life = 40-80 minutes

Adverse-effects

• common (> 10%)

• nausea/vomiting
• dizziness

• less common (1-10%)

• headache, pain at injection site, increased sweating, asthenia, malaise, hot flashes, anxiety, nervousness, dry mouth, tremor, insomnia, dyspnea, hyperventilation, abnormal crying, euphoria, depression, vision disorders

• uncommon (< 1%)

• shivering, hearing disorder, bradycardia, tachycardia, chest pain, hypertension, variations in blood pressure, hiccups, somnolence, thick tongue, ventricular asystoles, anxiety, sensation of coldness, generalized convulsions*, withdrawal syndrome

• * Be prepared to manage seizures prior to administration.

Drug-interactions

• toxic effects of tricyclic antidepressant overdose may emerge with reversal of benzodiazepine effect

Mechanism-of-action

• competitively antagonizes the effects of benzodiazepines on GABA-mediated inhibitory pathways in the CNS

More General Terms

• antidote

Additional Terms

• benzodiazepine
• tricyclic antidepressant (TCA)

Internet Database

PubChem: 3373

References

1. The Pharmacological Basis of Therapeutics, 9th ed. Gilman et al, eds. Permagon Press/McGraw Hill, 1996
2. Kaiser Permanente Northern California Regional Drug Formulary, 1998
3. Drug Information & Medication Formulary, Veterans Affairs, Central California Health Care System, 1st ed., Ravnan et al eds, 1998
4. Department of Veterans Affairs, VA National Formulary

flumazenil (Romazicon, Mazicon)