Belantamab Mafodotin-blmf (Blenrep)

These are some of the most common or most serious side effects of this medication. Talk with your provider about the side effects you are having and how they can be managed.

Platelets are blood cells that help your blood clot. Thrombocytopenia is when your platelet count is lower than normal, and you are at a higher risk of bleeding. Tell your providers if you have any bruising or bleeding, including nose bleeds, bleeding gums, or blood in your urine or stool. If your count gets too low, you may receive platelets from a donor. 

• Do not use a razor (an electric razor is fine).
• Do not do activities that can cause injury or bleeding.
• Talk to your provider before taking any non-steroidal, anti-inflammatory medications (NSAIDs) like Motrin/Advil (ibuprofen), Aleve (naproxen), Celebrex (celecoxib), and others. These can raise the risk of bleeding. 
• Use a soft-bristle toothbrush to brush your teeth. Ask your provider about flossing or using toothpicks. 

This medication can cause serious infections, with or without a decrease in white blood cell counts.

White blood cells (WBC) help your body fight infection. While you are having cancer treatment, your WBC count can drop, putting you at a higher risk of an infection. Tell your provider right away if you have a fever (a temperature greater than 100.4°F or 38°C), sore throat or cold, shortness of breath, cough, burning with urination, or a sore that doesn't heal.

Tips for preventing infection:

• Hand washing,  both yours and your visitors, is the best way to prevent the spread of infection.
• Avoid large crowds and people who are sick (those who have a cold, fever, or cough, or if someone you live with has these symptoms).
• When working outside, wear clothes that protect you, like long pants and gloves.
• Do not handle pet waste.
• Keep all cuts and scratches clean.
• Shower or bathe daily.
• Brush your teeth at least twice a day.
• Do not cut cuticles or ingrown nails. You may wear nail polish, but not fake nails.
• Ask your providers before scheduling dental appointments or procedures.

Ask your providers before you or someone you live with has any vaccines. 

You may have some symptoms that feel like you have a cold, such as a new or worsening cough and nasal congestion (stuffiness). These symptoms could be caused by an upper respiratory infection. Call for a temperature over 100.4°F or 38°C or as directed by your provider.

Anemia is when your red blood cell count is lower than normal. Red blood cells carry oxygen to the tissues in your body. When your red cell count is low, you may feel tired or weak. Tell your providers if you have shortness of breath, trouble breathing, or pain in your chest. If your count gets too low, you may receive a blood transfusion.

This medication can cause liver toxicity, or liver problems, which your provider may monitor for with blood tests called liver function tests. Symptoms may be:

• Yellowing of your skin or eyes.
• Dark or brown urine.
• Pain in your abdomen (belly).

Tell your provider if you have any of these symptoms.

This medication can cause kidney problems, like an increased creatinine level. Your provider may monitor for kidney problems with blood tests. Symptoms may be:

• Less urine output than normal.
• Blood in the urine.
• Swelling in the ankles.
• Loss of appetite.

Tell your provider if you have any of these symptoms.

Talk to your providers if you have nausea and/or vomiting. They can prescribe medications to help you. Making changes to your diet can also help. Avoid things that make your symptoms worse, like heavy or greasy/fatty foods and spicy or acidic foods, like tomatoes, lemons, and oranges. Try saltines or ginger ale to help your symptoms.  

Call your providers if you cannot keep fluids down for more than 12 hours or if you feel lightheaded or dizzy.

Diarrhea is when you pass three or more stools in a day. Your providers can suggest medications to relieve diarrhea. Do not take any medications to manage your diarrhea without talking to your provider first, as your stool may need to be tested. To manage it, try eating foods that are low in fiber and bland, like white rice and boiled or baked chicken. Try not to eat raw fruits, vegetables, whole grain breads, cereals, and seeds. Soluble fiber is a type of fiber found in some foods that helps absorb (soak up) fluid. Foods high in soluble fiber are applesauce, bananas (ripe), canned fruit, oranges, boiled potatoes, white rice, foods made with white flour, oatmeal, cream of rice, cream of wheat, and farina. Stay hydrated by drinking 8 to 10 glasses of non-alcoholic, non-caffeinated fluid each day.

Fatigue can cause exhaustion, feeling worn out and that your body is "heavy" and hard to move, or being unable to focus. It is common when you have cancer, and it is not the same as feeling tired. You may need to adjust your schedule to manage fatigue. Plan times to rest during the day and save your energy for more important activities. Exercise can help lessen fatigue. Talk to your providers about ways to deal with this side effect.

Some people may have a reaction during infusion of this medication. These can be:

• Chills.
• Fever.
• Low blood pressure.
• Nausea.
• Vomiting.

Your provider will monitor you for symptoms of infusion-related reactions. 

Pneumonitis is inflammation of the lungs. Tell your provider right away if you get any new or worsening symptoms, like:

• Shortness of breath.
• Trouble breathing.
• A cough.
• Fever.
   

This medication may affect your fertility. It can cause changes to your menstrual cycle or sperm. You may want to consider sperm banking or egg harvesting if you might wish to have a child in the future. Talk about your options with your provider before treatment.

There is a higher risk of health problems for your baby if you are pregnant, become pregnant, or get someone pregnant while on this medication. To lower the risk of birth defects, you should use birth control (contraception) to avoid pregnancy. Talk with your provider about what kind of birth control is safest for you and your partner.