Zulresso (brexanolone) is a prescription drug that’s prescribed to treat postpartum depression. It’s given by intravenous infusion in a special facility over a period of 60 hours.

Zulresso is prescribed for people ages 15 years and older to treat postpartum depression.

The active ingredient in Zulresso is brexanolone. Zulresso belongs to a group of drugs called neuroactive steroid gamma-aminobutyric acid (GABA) A receptor modulators.

This article describes the dosage of Zulresso, as well as its strength and how it’s given. To learn more about Zulresso, including Zulresso cost and side effects, see this in-depth article.

This section describes the usual dosage of Zulresso. Keep reading to learn more.

What is Zulresso’s form?

Zulresso is available as a liquid solution that’s given as an intravenous (IV) infusion (an injection into your vein over a period of time). It’s given by a trained healthcare professional at a certified healthcare facility.

What strength does Zulresso come in?

Zulresso comes in one strength of 100 milligrams (mg) per 20 milliliters (mL) of solution (5 mg/mL).

What are the usual dosages of Zulresso in adults?

Zulresso is given by a healthcare professional as an IV infusion over 60 hours. Your doctor will start you on a low dose of Zulresso for several hours, before your dosage is gradually increased over several more hours. Then your Zulresso dosage will be lowered again several hours before your treatment ends.

The information below describes dosages that are commonly used or recommended. In some cases, doctors may adjust your dosage from those shown below.

Dosage for postpartum depression

Zulresso dosage for adults with postpartum depression is based on your body weight in kilograms (kg). For reference, one kg equals about 2.2 pounds (lb).

You’ll receive Zulresso as an intravenous (IV) infusion over 60 hours (2.5 days). It will be given by a healthcare professional at a certified Zulresso Risk Evaluation and Mitigation Strategies (REMS) program facility.

The Zulresso dosage schedule is:

  • Starting dosage for 0 to 4 hours: 30 micrograms (mcg) per kg per hour
  • Dosage for 4 to 24 hours: 60 mcg/kg per hour
  • Dosage for 24 to 52 hours: 90 mcg/kg per hour, or 60 mcg/kg per hour for those who cannot tolerate the 90 mcg/kg dosage
  • Dosage for 52 to 56 hours: 60 mcg/kg per hour
  • Dosage for 56 to 60 hours: 30 mcg/kg per hour

Talk with your doctor if you have questions about your dosage. You can also learn more about Zulresso treatment and support resources available from the manufacturer’s website.

What’s the dosage of Zulresso for children?

Zulresso is prescribed to help treat postpartum depression in children ages 15 years and older.

The dosage used in children is the same as the dosage for adults. To learn more, see the “What are the usual dosages of Zulresso?” section above.

For more information about Zulresso’s dosage for children, talk with your child’s doctor.

How Zulresso is given?

Zulresso is given as an intravenous (IV) infusion at a certified healthcare facility by a healthcare professional. It’s administered through a Zulresso REMS program. This is because the drug can cause serious side effects, including severe sleepiness and loss of consciousness. (See the boxed warning section for more details.)

You’ll receive your Zulresso infusion over a period of 60 hours. Your doctor will monitor you carefully while you receive the medication. If you experience serious side effects from the medication, they may pause treatment, lower your dose, or stop treatment altogether.

Talk with your doctor if you have questions about Zulresso’s dosage.

Is Zulresso used long term?

No, it’s not used long term. Zulresso is given only one time over a 60-hour period to treat postpartum depression. It’s not known whether it’s safe or effective to use Zulresso more than one time.

If you have questions about your dosage and how long you’ll receive Zulresso, talk with your doctor to learn more.

Below are answers to some commonly asked questions about Zulresso’s dosage.

What is Zulresso’s dosage while breastfeeding?

There is no separate dosage for Zulresso if you’re breastfeeding during treatment. You would receive the typical dosage described above.

A small study found that Zulresso does pass into breast milk but at very low levels. The drug is likely safe to receive while breastfeeding.

If you’re planning to breastfeed while being treated with Zulresso, talk with your doctor. They can tell you more about the safety of Zulresso use while breastfeeding.

How long does it take Zulresso to start working?

Zulresso is given as a continuous IV infusion over 60 hours. The drug starts to work soon after you begin treatment. In studies of the medication, most people had symptom relief within 2 hours of starting Zulresso.

If you have other questions about what to expect with your Zulresso treatment, talk with your doctor.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.