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Generic Name: remimazolam (REM i MAZ oh lam)
Brand Name: Byfavo

Medically reviewed by on March 18, 2021. Written by Cerner Multum.

What is Byfavo?

Byfavo injection is a benzodiazepine (ben-zoe-dye-AZE-eh-peen) that is used to sedate a person who is having a minor surgery, dental work, or other medical procedure.

Byfavo injection may also be used for purposes not listed in this medication guide.


Tell your doctor about all your current medicines Byfavo can slow or stop your breathing, especially if you have recently used an opioid medicine, alcohol, or other drugs that can slow your breathing.

Tell your doctor about all your medical conditions or allergies, or if you are pregnant or breastfeeding.

Before taking this medicine

You should not be treated with Byfavo if you are allergic to Byfavo or dextran 40.

Tell your doctor or caregivers if you recently used alcohol, sedatives, tranquilizers, or opioid medications.

Byfavo may harm an unborn baby, and generally should not be used during pregnancy.

You should not breastfeed within 5 hours after receiving Byfavo. If you use a breast pump during this time, throw out any milk you collect. Do not feed it to your baby.

How is Byfavo given?

Byfavo is given as an infusion into a vein. You will receive this injection in a medical, dental, or surgical setting.

Byfavo is usually given as a single dose just before a surgery or medical procedure.

Byfavo can make you very drowsy, dizzy, or light-headed. These effects may last longer in older adults. Use caution to avoid falling or accidental injury after you have received this medicine injection. You may need help getting out of bed for several hours.

After treatment with Byfavo injection, you will be watched to make sure the medication is working and does not cause harmful side effects. Your breathing, blood pressure, oxygen levels, and other vital signs will be watched closely.

What happens if I miss a dose?

Because you will receive Byfavo in a clinical setting, you are not likely to miss a dose.

What happens if I overdose?

Since this medication is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

What should I avoid after receiving Byfavo?

Do not drink alcohol shortly after receiving Byfavo.

Byfavo injection can cause extreme drowsiness that may last for several hours after you have received the medication. Older adults may feel sleepy for even longer.

Avoid driving or doing anything that requires you to be awake and alert until the effects of Byfavo have worn off completely.

Byfavo side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Byfavo can slow or stop your breathing, especially if you have recently used an opioid medication, alcohol, or other drugs that can slow your breathing. Your caregivers will watch you for symptoms such as weak or shallow breathing.

Tell your caregivers right away if you have:

  • weak or shallow breathing;

  • confusion;

  • slow heartbeats; or

  • a light-headed feeling, like you might pass out.

The sedative effects of remimazolam may last longer in older adults. Accidental falls are common in elderly patients who use benzodiazepines.

Common side effects may include:

  • feeling light-headed;

  • shallow breathing; or

  • changes in blood pressure.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Byfavo?

Shortly after you are treated with Byfavo, using other drugs that make you sleepy or slow your breathing can cause dangerous side effects or death. Ask your doctor before using opioid medicine, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.

Other drugs may affect Byfavo, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.