Plerixafor (Mozobil®)

Author: Marisa Healy, BSN, RN
Content Contributor: Oxana Megherea, PharmD - Oncology Clinical Pharmacy Specialist
Last Reviewed: March 19, 2026

Pronounce: pler-IX-a-fore

Classification: Hematopoietic stem cell mobilizer

About Plerixafor (Mozobil®)

Plerixafor is used to mobilize, or move, stem cells from your bone marrow to your bloodstream. Plerixafor is used with a granulocyte-colony stimulating factor (G-CSF) before an autologous stem cell transplant. The G-CSF is given first for 4 days to help your bone marrow make more stem cells and white blood cells. You will then receive plerixafor daily for up to 4 days to make these stem cells easier to collect so they can be transplanted back into your body.

Plerixafor is not a chemotherapy medication but is used in preparation for some autologous stem cell transplants. Talk with your provider about whether plerixafor will be used before your transplant.

How to Take Plerixafor

Plerixafor is given as a subcutaneous injection (SQ, given under the skin). It will be given about 11 hours before you are scheduled to have your blood drawn to collect your cells before your transplant (called apheresis).

Tell your provider about all medications and supplements you take. Tell your provider if you have a history of leukemia.

Your blood work will be monitored before your autologous stem cell transplant. Your provider will pay close attention to your white blood cells.

Possible Side Effects

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.

Diarrhea

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.

Nausea and/or Vomiting

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.

Injection Site Irritation

You may have irritation or injury where this medication was injected (put into your body). You may have pain, bruising, or bleeding. Call your provider if these symptoms do not get better or get worse as time goes on.

Fatigue

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.

Headache

Your provider can recommend medications and other strategies to help relieve pain.

Allergic Reactions

Some people may have an allergic reaction to this medication. Signs of an allergic reaction are:

  • Shortness of breath or trouble breathing.
  • Chest pain.
  • Rash.
  • Itching.
  • Flushing (reddening of the skin, often on the face, neck, or chest).
  • A drop in blood pressure (you may feel lightheaded, dizzy, or weak).

If you have any of these signs while you are getting an infusion, tell your provider right away. The infusion will be slowed down or stopped. Depending on your reaction, you may still be able to get the medication if you are given medicine to prevent a reaction or if the medication is given at a slower rate.

Low Platelet Count (Thrombocytopenia)

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. 

Spleen Problems

The spleen is an organ in your belly that stores and filters blood and helps fight infection. This medication can make your spleen larger and can cause it to rupture (break open). Call your provider right away if you have pain on the left side of your abdomen (belly) or shoulder pain.

Reproductive Concerns

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. 

If you can become pregnant, you will need to use effective birth control during treatment and for 1 week after the last dose of this medication, even if your menstrual cycle has stopped or changed. If you can get someone pregnant, you will need to use effective birth control during treatment and for 1 week after the last dose of this medication, even if you believe you are not producing sperm. You should not breastfeed during treatment and for 1 week after the last dose of this medication.