Jeffrey Panko NP Psychiatry · Patient education
Flumazenil
Clinician-administered IV benzodiazepine reversal
A guide for adults receiving flumazenil.
Follow the instructions from your treating healthcare team.
Formulations: An IV injection is given in small, reassessed doses by the treating team. There is no take-home dosing regimen.
What it is used for
Flumazenil reverses some effects of benzodiazepines after procedures or in selected overdose situations. It is administered by clinicians with monitoring and emergency support. It is not a home rescue medication.
How it works
It blocks benzodiazepine binding at GABA-A receptors. Reversal can restore alertness, but it can also abruptly remove seizure protection or trigger withdrawal in a person who is physically dependent.
What to expect over time
Reversal may occur within minutes. Its effects can wear off before the benzodiazepine, so repeat sedation or breathing problems remain possible.
Taking your medication
- Tell the team about regular benzodiazepine use, seizures, and all substances that may have been taken.
- Remain for the required observation even if you feel awake. Sedation can return after flumazenil wears off.
- Follow discharge restrictions for driving, alcohol, and other sedatives.
When to get help
Emergency symptoms. Tell staff immediately about twitching, a seizure, breathing difficulty, chest symptoms, or return of profound sleepiness. Call 911 if severe symptoms occur after discharge.
Prompt medical advice. Report renewed drowsiness, confusion, agitation, or withdrawal symptoms. Do not take extra medication to counteract these effects without instructions.
If you feel unsafe or have thoughts of self-harm, call 911 or go to an emergency department.
Possible side effects
- Nausea, dizziness, or headache
- Anxiety, agitation, or sweating
- Injection-site discomfort
- Seizures or acute withdrawal in susceptible patients
Keeping track of treatment
Some side effects resolve with time; others may require a change of medication. Discuss persistent or bothersome side effects with your provider.
Staff monitor breathing, oxygen, pulse, blood pressure, alertness, and seizure activity. Support of the airway and breathing remains central to overdose care.
If you take too much
For a suspected overdose, call Poison Control at 1-800-222-1222 immediately, even if you feel well. Call 911 for a seizure, collapse, trouble breathing, or inability to wake.
Before you start
Regular benzodiazepine use, seizure disorders, and mixed overdoses—especially involving tricyclic antidepressants—can make flumazenil dangerous. It is contraindicated in certain situations where a benzodiazepine is controlling a life-threatening condition.
Medicines and interactions
Review all your medications with your provider, including over-the-counter medicines and supplements. Have new medications checked before taking them.
The main concern is what substances are already present and whether benzodiazepine effects are protective. Give the team complete information about antidepressants, opioids, sedatives, alcohol, and other exposures.
Everyday tips
Bring medication containers or a medication list when available.
Follow the discharge plan and arrange a responsible adult or transportation when instructed.
Your questions answered
Should everyone with a benzodiazepine overdose receive it?
No. In some situations it can cause seizures or dangerous withdrawal. Clinicians weigh the risks and use supportive treatment when appropriate.
Does waking up mean the overdose is over?
No. The original medication or other substances may still be active. Observation is necessary.
Storage and safety
Flumazenil is stored and administered in clinical care. Do not seek an unverified preparation for home use.
Sources
About this information
Educational handout; does not replace your prescription or provider's recommendations.
Educational inclusion does not mean this medication or its indications are treated at this practice. Review the guide for your exact product with your prescriber or pharmacist.