Brixadi (buprenorphine) is a prescription injection that’s used to treat opioid use disorder (OUD). It comes as a solution in prefilled syringes and is given weekly or monthly by a healthcare professional.

Brixadi is prescribed to treat moderate to severe opioid use disorder (OUD) in adults. It’s part of a complete treatment program that includes counseling and psychotherapy.

The active ingredient in Brixadi is buprenorphine. (An active ingredient is what makes a drug work.) It belongs to a group of drugs called partial opioid agonists.

This article describes the dosages of Brixadi, as well as its strengths and how it’s given. To learn more about Brixadi, see this in-depth article.

This section describes the usual dosages of Brixadi. Keep reading to learn more.

What is Brixadi’s form?

Brixadi comes as a liquid solution in a single-dose, prefilled syringe.

What strengths does Brixadi come in?

Brixadi comes in several strengths. Strengths are listed in milligrams (mg) of Brixadi per milliliter (mL) of liquid solution.

Syringes for weekly Brixadi injections are available in four strengths:

  • 8 mg/0.16 mL
  • 16 mg/0.32 mL
  • 24 mg/0.48 mL
  • 32 mg/0.64 mL

Syringes for monthly Brixadi injections are available in three strengths:

  • 64 mg/0.18 mL
  • 96 mg/0.27 mL
  • 128 mg/0.36 mL

What are the usual dosages of Brixadi?

Your doctor will decide the best dosage and dosing schedule for you. This depends on the severity of your condition and other factors, such as how you respond to treatment and whether you’ve been on buprenorphine treatment before. (Buprenorphine is the active ingredient in Brixadi.)

The information below describes dosages that are commonly used or recommended. Your doctor will determine the best dosage that works for you.

Dosage for opioid use disorder

Brixadi is an extended-release drug. It’s slowly released into your body over a long period of time. It may be given as an injection every 7 days (weekly) or as an injection every 28 days (monthly).

If you’re not already taking buprenorphine, you’ll first need to take a test dose of generic buprenorphine as a sublingual tablet (SLT)* before starting treatment with Brixadi. This allows your doctor to adjust your Brixadi treatment as needed to best manage any withdrawal symptoms. Your doctor will slowly increase your Brixadi dosage over the first week of treatment.

Your doctor will decide whether a weekly or monthly schedule is right for you. Your doctor may prescribe:

  • Weekly injections. You may be prescribed Brixadi weekly injections if you don’t experience withdrawal symptoms following a 4-mg test dose of buprenorphine SLT or if you’re already taking buprenorphine SLT.
  • Monthly injections. You may be prescribed Brixadi monthly injections if you’ve been on a stable dose of buprenorphine SLT for some time.

The table below describes the usual dosages of Brixadi when switching from buprenorphine SLT.

Buprenorphine SLT dose, dailyBrixadi dose, weeklyBrixadi dose, monthly
6 mg or less8 mg
8–10 mg16 mg64 mg
12–16 mg24 mg96 mg
18–24 mg32 mg128 mg

If your doctor decides to switch your treatment from weekly to monthly, or vice versa, the table below shows how the dosage will change with the schedule change.

Weekly doseMonthly dose
16 mg64 mg
24 mg96 mg
32 mg128 mg

Your doctor will monitor you while you’re on Brixadi treatment and will adjust your dosage as needed.

The usual maintenance dosage is 24 mg per week or 96 mg per month. And the maximum dosage is 32 mg per week or 128 mg per month.

* An SLT is a tablet that dissolves under your tongue.

Is Brixadi used long term?

Yes, Brixadi is typically used as a long-term treatment. If you and your doctor determine that it’s safe and effective for your condition, you’ll likely receive Brixadi injections long term.

Dosage adjustments

In some cases, your doctor may need to adjust your dosage of Brixadi.

If you have moderate to severe liver disease, it’s likely that Brixadi will build up in your body. In this case, your doctor will likely recommend a different treatment for you.

If you develop liver problems while on Brixadi treatment, your doctor will monitor you for side effects and signs of overdose. They may recommend that you stop treatment with Brixadi and switch to a safer treatment option.

The dosage of Brixadi you’re prescribed may depend on several factors. These include:

  • the severity of the condition Brixadi is being used to treat
  • other medications you may be taking
  • other conditions you may have (see the “Dosage adjustments” section)

Your doctor or another healthcare professional will inject Brixadi under the skin of your thigh, abdomen, upper arm, or buttock. You’ll receive these injections either weekly or monthly.

Brixadi has a boxed warning about the risk of serious harm if injected into a vein. Injecting Brixadi into a vein can cause serious side effects, including tissue damage, blood clots, or even death. Because of this risk, Brixadi is only given by a healthcare professional through the Brixadi Risk Evaluation and Mitigation Strategy (REMS) program.

If you haven’t been taking buprenorphine before starting Brixadi, your doctor will recommend that you receive the Brixadi injections under the skin of your thigh, abdomen, or buttock. This is because studies of the drug have shown that the drug isn’t absorbed as well when injected into the upper arm. As you progress in your treatment and your body becomes less dependent on opioids, you may also receive the injection under the skin of your upper arm.

It’s recommended that you have naloxone (Narcan) available during your treatment with Brixadi. Taking an opioid, benzodiazepine, or other central nervous system depressant with Brixadi raises the risk of experiencing opioid overdose effects, such as respiratory depression (slow, shallow breathing) and coma. Narcan is a nasal spray that can be used in an emergency to treat an opioid overdose. If you have Narcan, let your family and companions know where they can find it in an emergency. And let them know that if they give you Narcan to treat an opioid overdose, you’ll still need medical care. They should call 911 or take you to the nearest emergency room.

If you miss an appointment to receive a dose of Brixadi, call your doctor’s office as soon as possible to reschedule. Weekly doses of Brixadi are given every 7 days, and monthly doses are given every 28 days. It’s important to receive doses of Brixadi as scheduled to keep steady levels of the drug in your body.

If you need help remembering your appointments, try setting an alarm or downloading a reminder app on your phone.

Receiving Brixadi as a long-term treatment can lead to dependence. With dependence, your body needs a drug to function as usual.

If you suddenly lower your dose or stop treatment, you may experience withdrawal symptoms. These are side effects that can occur when you stop taking a drug your body has become dependent on.

Brixadi is a partial opioid agonist. Withdrawal symptoms from Brixadi are milder than from other opioids. They also tend to take some time to appear. Typical opioid withdrawal symptoms can include diarrhea and vomiting, sweating, and tremors (shaking). Similar but milder symptoms are possible after stopping Brixadi.

When you and your doctor decide it’s time to stop your Brixadi treatment, your doctor will likely lower your dosage slowly over time. This can help reduce your risk of withdrawal symptoms.

If you have questions about Brixadi and the risk of dependence or withdrawal symptoms, talk with your doctor.

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

Is Brixadi’s dosage similar to Vivitrol’s dosage?

No. Although Brixadi and Vivitrol (naltrexone) are both used to treat opioid use disorder, they don’t come in the same form and are administered in different ways. They also have differences in their dosing schedule options.

Brixadi comes as a liquid solution inside a prefilled syringe. A healthcare professional will administer it as an injection under the skin once per week or once per month.

Vivitrol comes as a powder in a vial that’s mixed with a liquid to make a solution. A healthcare professional will inject Vivitrol into a muscle once per month.

To learn more about how these drugs compare, talk with your doctor.

How long does it take for Brixadi to start working?

Brixadi starts to work after your first dose. Your doctor will monitor you carefully when you begin treatment with Brixadi to make sure the drug is working to treat your condition and that you don’t experience withdrawal symptoms. They may adjust your dose based on how you respond to treatment.

If you’re experiencing withdrawal symptoms while on Brixadi, talk with your doctor. Don’t take other opioids while you’re on Brixadi treatment. Taking other opioids could cause overdose or even death.

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

The sections above describe the usual dosages provided by the manufacturer. If your doctor recommends Brixadi for you, they’ll prescribe the dosage that’s right for you.

Talk with your doctor if you have questions or concerns about your current dosage.

Here are some examples of questions you may want to ask your doctor:

  • What dosage of Brixadi will my doctor prescribe if I’m switched from another medication for opioid use disorder?
  • How does the dosage of Brixadi compare with the dosage of Sublocade (buprenorphine)?
  • What are the pros and cons of the weekly dosing schedule versus the monthly dosage schedule for Brixadi?

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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.