Muromonab-CD3 lowers your body's immune system. The immune system helps your body fight infections. The immune system can also fight or "reject" a transplanted organ such as a kidney. This is because the immune system treats the new organ as an invader.

Muromonab-CD3 is used with other medications to prevent organ rejection after a kidney transplant.

Muromonab-CD3 may also be used for other purposes not listed in this medication guide.

Muromonab-CD3 is given as an injection through a needle placed into a vein. You will receive this injection just before your transplant and again 4 days afterward. The medicine must be given slowly through an IV infusion, and can take up to 30 minutes to complete.

Some people receiving a muromonab-CD3 injection have had a reaction to the infusion (within 30 to 60 minutes after the medicine is injected into the vein). Tell your caregiver right away if you feel chilled or feverish, nauseated, weak, shaky, or light-headed, or if you have a headache, or joint and muscle aches. These side effects may also occur up to several hours after your injection.

Muromonab-CD3 can lower the blood cells that help your body fight infections. This can make it easier for you to bleed from an injury or get sick from being around others who are ill. To be sure your blood cells do not get too low, your blood will need to be tested on a regular basis. It is important that you not miss any scheduled visits to your doctor after your transplant.

Avoid contact with people who have colds, the flu, or other contagious illnesses. Contact your doctor immediately if you develop signs of infection.

Avoid receiving a vaccine or flu shot shortly after you have been treated with muromonab-CD3, unless your doctor has told you to.

There may be other drugs that can affect muromonab-CD3. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

You should not be given this medication if you are allergic to muromonab or mouse proteins, or if you have:

• heart failure;

• untreated or uncontrolled high blood pressure (hypertension);

• epilepsy or other seizure disorder; or

• if you are pregnant or breast-feeding.

Before receiving muromonab-CD3, tell your doctor if you are allergic to any drugs, or if you have:

• chest pain (angina);

• congestive heart failure;

• a breathing disorder;

• a history of heart attack or stroke; or

• if you have recently taken a diuretic ("water pill").

If you have any of these conditions, you may need a dose adjustment or special tests to safely receive muromonab-CD3.

FDA pregnancy category C. This medication may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

It is not known whether muromonab-CD3 passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.