Rusfertide

This information from UpToDate^® Lexidrug^™ explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

Brand Names: US

Mimrylo

What is this drug used for?

• It is used to treat high red blood cell levels in people with polycythemia vera (PV).

What do I need to tell my doctor BEFORE I take this drug?

• If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
• If you are breast-feeding. Do not breast-feed while you take this drug and for 30 days after your last dose.

This drug may interact with other drugs or health problems.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take this drug?

• Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
• Have your blood work and other lab tests checked as you have been told by your doctor.
• This drug may cause harm to an unborn baby. A pregnancy test will be done before you start this drug to show that you are NOT pregnant.
• If you may become pregnant, use birth control while taking this drug and for 30 days after your last dose. If you get pregnant, call your doctor right away.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Feeling very tired or weak.
• This drug may increase your blood platelet levels. Call your doctor right away if you have signs of bleeding or blood clots like any unexplained bruising or bleeding, chest pain, shortness of breath, leg pain or swelling, or sudden severe headache.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Bruising, itching, pain, redness, swelling, hard skin, or other irritation have happened where the injection was given. If this happens, your doctor may have you apply ice packs or give you another drug to take for the reaction. Be sure you know what to do if you have a reaction at the injection site.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to your national health agency.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

How is this drug best taken?

Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.

• It is given as a shot into the fatty part of the skin on the top of the thigh or the belly area.
• This drug may be given into the outer area of the upper arm if given by someone else.
• If you will be giving yourself the shot, your doctor or nurse will teach you how to give the shot.
• Wash your hands before and after use.
• You will need to mix this drug before giving a dose. The powder in the vial is the drug. You must mix it with the solution in the syringe.
• Gently swirl to mix. Do not shake.
• This drug is clear and colorless. Do not use if it changes color. Do not use if the solution is cloudy, leaking, or has particles.
• Move the site where you give the shot with each shot.
• Do not give into skin within 2 inches (5 cm) of the belly button.
• Do not give into skin that is irritated, tender, bruised, red, scaly, hard, scarred, or has stretch marks.
• After mixing, you may keep this drug at room temperature for up to 4 hours. If you do not use this drug within 4 hours after mixing, throw it away.
• Each vial and prefilled diluent syringe is for 1 use only. Throw away any part of the vial or prefilled syringe after the dose is given.
• If you drop the prefilled syringe with the cap off, do not use it. Throw it away.
• Throw away needles in a needle/sharp disposal box. Do not reuse needles or other items. When the box is full, follow all local rules for getting rid of it. Talk with a doctor or pharmacist if you have any questions.

What do I do if I miss a dose?

If taking 1 time per week:

• If you miss a dose by 1 to 4 days, take the missed dose right away and go back to your normal time.
• If you miss a dose by more than 4 days, take the missed dose right away. Take the next dose 3 days later. Then go back to your normal time.

If taking 2 times per week:

• If you miss a dose by 1 to 2 days, take the missed dose right away. Take the next dose 3 days later. Then go back to your normal time.
• If you miss a dose by more than 2 days, skip the missed dose and go back to your normal time.

For all patients taking this drug:

• If you are not sure what to do if you miss a dose, call your doctor.
• Do not take 2 doses at the same time or extra doses.

How do I store and/or throw out this drug?

• Store at room temperature in a dry place. Do not store in a bathroom.
• Do not freeze.
• Store in the original container to protect from light.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

General drug facts

• If your symptoms or health problems do not get better or if they become worse, call your doctor.
• Do not share your drugs with others and do not take anyone else’s drugs.
• Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
• Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
• If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.

Last Reviewed Date

2026-09-03

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