Rebif (interferon beta-1a) is a brand-name drug that’s prescribed for certain forms of multiple sclerosis (MS) in adults. Rebif comes as a liquid solution that’s typically self-injected three times per week. The dosage can vary depending on what condition the drug is used to help treat.
Rebif is approved by the Food and Drug Administration (FDA) to treat:
Rebif is a biologic and belongs to a drug class called interferons. Rebif is not available in a biosimilar version.
Keep reading for specific information about the dosage of Rebif, including its strengths and how to use the medication. For a comprehensive look at Rebif, see this article.
Note: This article describes typical dosages for Rebif provided by the drug’s manufacturer. When taking Rebif, always follow the dosage prescribed by your doctor.
Read below for recommended dosages of Rebif and other details about the drug.
Rebif forms
Rebif is given as a subcutaneous injection. It comes as a liquid solution in the following forms:
- single-dose pre-filled autoinjectors
- single-dose pre-filled syringe
Your doctor will show you how to self-inject your Rebif dosage.
Rebif strengths
Rebif autoinjector and prefilled syringe both come in three strengths:
- 8.8 micrograms (mcg) per 0.2 milliliters (mL)
- 22 mcg per 0.5 mL
- 44 mcg per 0.5 mL
Typical dosages
Typically, your doctor will first prescribe you a starter dosage. They’ll adjust it over time to reach the amount that’s right for you. Your doctor will ultimately prescribe the smallest dosage that provides the desired effect.
The following information describes dosages that are commonly prescribed in adults. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.
Dosage for multiple sclerosis
Doctors may prescribe Rebif to treat certain forms of MS.
If your doctor prescribes Rebif for MS, your target dose will be either 22 mcg or 44 mcg.
If your target dose is 22 mcg:
Your starting dose will likely be 4.4 mcg. Typically, you’ll administer this three times per week on Monday, Wednesday, and Friday. This allows at least 48 hours between each dose. It is best to inject Rebif in the late afternoon or early evening.
After 2 weeks, your doctor may recommend increasing your dose to 11 mcg. Then, in another 2 weeks, they will likely increase it to a target maintenance dosage of 22 mcg. This is the typical recommended dosage of Rebif for some people with MS.
If this dose isn’t working for you, your doctor may recommend another dose increase, up to 44 mcg to treat MS. This is the maximum dose of Rebif that’s recommended.
The table below shows the typical titration dosage schedule, including the starting dosage and maintenance dosage. Your doctor will choose a maintenance dosage that suits your needs.
Dosage titration schedule for 22 mcg dosage
| Week of treatment | Dosage | Amount of syringe/autoinjector to use |
|---|---|---|
| Week 1 | 4.4 mcg | Use one half of an 8.8 mcg syringe. |
| Week 2 | 4.4 mcg | Use one half of an 8.8 mcg syringe. |
| Week 3 | 11 mcg | Use one half of a 22 mcg syringe. |
| Week 4 | 11 mcg | Use one half of a 22 mcg syringe. |
| Week 5 and after (maintenance dosage) | 22 mcg | Use one full 22 mcg syringe or autoinjector. |
If your target dose is 44 mcg:
Your starting dose will likely be 8.8 mcg. Typically, you’ll administer this three times per week on Monday, Wednesday, and Friday. This allows at least 48 hours between each dosage. It is best to inject Rebif in the late afternoon or early evening.
After 2 weeks, your doctor may recommend increasing your dosage to 22 mcg. Then, in another 2 weeks, they will likely increase it to a target dose of 44 mcg. This is the typical recommended dosage of Rebif for some people with MS. This is also the maximum dose of Rebif that’s recommended.
The table below shows the typical titration dosage schedule, including the starting dosage and maintenance dosage. Your doctor will choose a maintenance dosage that suits your needs.
Dosage titration schedule for 44 mcg dosage
| Week of treatment | Dosage | Amount of syringe/autoinjector to use |
|---|---|---|
| Week 1 | 8.8 mcg | Use one full 8.8 mcg syringe or autoinjector. |
| Week 2 | 8.8 mcg | Use one full 8.8 mcg syringe or autoinjector. |
| Week 3 | 22 mcg | Use one full 22 mcg syringe or autoinjector. |
| Week 4 | 22 mcg | Use one full 22 mcg syringe or autoinjector. |
| Week 5 and after (maintenance dosage) | 44 mcg | Use one full 44 mcg syringe or autoinjector. |
For more information about your specific dosage, talk with your doctor.
Long-term treatment
Rebif is meant to be used as a long-term treatment. If you and your doctor determine that Rebif is safe and effective for you, you’ll likely use it long term.
Before you start taking Rebif, your doctor will discuss your treatment plan with you.
The Rebif dosage your doctor prescribes will depend on several factors. These include:
- your age
- how your body responds to Rebif
- the type and severity of your MS
- side effects you may have with Rebif
- your liver and kidney function
Other medical conditions you have can also affect your Rebif dosage.
Dosage adjustments
Your doctor may need to adjust your dosage if you have liver damage or kidney disease, or if you’re age 65 years or older.
Be sure to tell your doctor about all medications you take and any health conditions you may have.
Rebif comes as a liquid solution in single-dose prefilled syringes or autoinjectors. It’s given as a subcutaneous injection.
With a subcutaneous injection, you’ll inject the medication under your skin. You’ll use the single-dose prefilled syringe or the autoinjector to give yourself Rebif. Your doctor will administer your first dose. Then, they’ll show you (or your caregiver) how to do it. Make sure to inject Rebif according to your prescribed instructions.
You’ll store Rebif pens or autoinjectors in the refrigerator. Rebif can be stored at room temperature (out of heat and light) for up to 30 days, but if you store it at room temperature, you’ll need to throw any remaining Rebif away after 30 days.
You can self-inject Rebif into your abdomen, the top of your thigh, your outer buttocks, or your upper arm. If you inject into your abdomen, do not inject Rebif within 2 inches of your belly button.
Be sure to choose a different injection site each time you inject Rebif. And avoid areas where your skin is tender, hard, or irritated. This will reduce your risk of injection-related side effects, such as bleeding or pain at the injection site.
General guidance:
If you have questions about how to use Rebif, talk with your doctor or pharmacist. There’s also a helpful video and step-by-step instructions on the manufacturer’s website.
If you miss a dose of Rebif, inject it as soon as you remember. Then, take your next Rebif dose at least 48 hours later. Do not inject Rebif 2 days in a row. If you’re not sure whether you should inject a missed dose or skip it, talk with your doctor or pharmacist.
To help make sure that you don’t miss a dose, try using a medication reminder. This can include setting an alarm or putting a note where you’ll see it, such as on your bathroom mirror or bedside table. You could also download a reminder app on your phone.
It’s important that you do not use more Rebif than your doctor prescribes. For some medications, taking more than the recommended amount may lead to harmful effects or overdose.
If you take more than the recommended amount of Rebif
Call your doctor right away if you believe you’ve taken too much Rebif. Another option is to call America’s Poison Centers at 800-222-1222 or use its online tool. If you have severe symptoms, immediately call 911 or your local emergency number, or go to the nearest emergency room.
Below are some frequently asked questions about Rebif.
How long does it take for Rebif to start working?
Rebif starts to work after your first dose. Because of how the drug works, you likely won’t feel the drug working in your body. But your doctor will monitor you during treatment to check whether the drug is working to treat your condition.
Over time, you may also notice fewer symptoms and flare-ups from your condition due to your Rebif treatment.
Talk with your doctor if you have questions about what to expect with Rebif treatment.
Is there a typical dosage range for Rebif?
Yes, the typical recommended dosage range for Rebif in the titration phase ranges from 4.4–22.0 mcg three times per week until you reach a target maintenance dosage of either 22 mcg or 44 mcg three times per week.
For more information about Rebif dosages, see the “Rebif dosage” section above. You can also talk with your doctor or pharmacist.
The dosages in this article are typical dosages provided by the drug’s manufacturer. If your doctor recommends Rebif for you, they will prescribe the dosage that’s right for you. Always follow the dosage that your doctor prescribes.
As with any drug, never change your dosage of Rebif without your doctor’s recommendation. If you have questions about the dosage of Rebif that’s best for you, talk with your doctor.
Besides learning about dosage, you may want other information about Rebif. These additional articles might be helpful:
- More about Rebif: For information about other aspects of Rebif, refer to this article.
Disclaimer: Medical News Today 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.