Kesimpta Side Effects

Generic name: ofatumumab

Medically reviewed by Philip Thornton, DipPharm. Last updated on Jun 4, 2024.

Note: This document provides detailed information about Kesimpta Side Effects associated with ofatumumab. Some dosage forms listed on this page may not apply specifically to the brand name Kesimpta.

Applies to ofatumumab: solution.

Precautions

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly and to check for unwanted effects. Blood and urine tests may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant during treatment and for at least 6 months after the last dose of this medicine. If you think you have become pregnant while using the medicine, tell your doctor right away.

This medicine may cause chest pain, fever, chills, itching, hives, flushing of the face, rash, dizziness, fainting, or lightheadedness, trouble breathing, or swelling of the face, tongue, and throat within a few hours after you receive it. Check with your doctor or nurse right away if you have any of these symptoms.

This medicine may cause a serious type of reaction called tumor lysis syndrome. Your doctor may give you a medicine to help prevent this. Call your doctor right away if you have a decrease or change in urine amount, joint pain, stiffness, or swelling, lower back, side, or stomach pain, a rapid weight gain, swelling of the feet or lower legs, or unusual tiredness or weakness.

Ofatumumab can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:

• If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
• Check with your doctor immediately if you notice any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.
• Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
• Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
• Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
• Avoid contact sports or other situations where bruising or injury could occur.

This medicine may increase your risk of developing a serious and rare brain infection called progressive multifocal leukoencephalopathy (PML). Check with your doctor right away if you have vision changes, loss of coordination, clumsiness, memory loss, difficulty speaking or understanding what others say, and weakness in the legs.

This medicine may cause hepatitis B virus reactivation. Check with your doctor right away if you have any symptoms of liver problems, including yellow skin or eyes, dark brown-colored urine, right-sided stomach pain, fever, or severe tiredness.

Do not have any live vaccines (immunizations) while you are being treated with ofatumumab (the active ingredient contained in Kesimpta) injection. You should have completed any needed immunizations at least 4 weeks for live or live-attenuated vaccines and at least 2 weeks for non-live (inactivated) vaccines before starting treatment with this medicine. Check with your doctor before having any vaccines.

Do not take other medicines unless thy have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Serious side effects of Kesimpta

Along with its needed effects, ofatumumab may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking ofatumumab:

Check with your doctor immediately if any of the following side effects occur while taking ofatumumab:

Other side effects of Kesimpta

Some side effects of ofatumumab may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

See also:

Frequently asked questions

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Further information

Kesimpta side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer