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Generic name: muromonab-cd3 [ MUE-roe-MOE-nab-CD-3 ]
Brand name: Orthoclone OKT 3

Muromonab-CD3 may cause serious allergic reactions. These may occur at any time while you use muromonab-CD3. It may also cause other serious and sometimes fatal effects, including heart and nervous system problems. Tell your doctor right away if you experience shortness of breath; chest pain; numbness of an arm or leg; sudden severe dizziness, headache, nausea, or vomiting; fainting; severe stomach pain; trouble speaking; vision changes (eg, light sensitivity or blindness); one-sided weakness; seizures; or paralysis after you receive muromonab-CD3.

You should only receive muromonab-CD3 in a health care facility where you can receive proper treatment in case you have a severe allergic reaction or other severe side effects.

Your doctor may give you another medicine (methylprednisolone) to help lower the risk of certain severe side effects from muromonab-CD3.

Muromonab-CD3 is used for:

Treating organ rejection after a kidney transplant. It is also used to treat organ rejection in patients with a heart or liver transplant if corticosteroids do not work well. It may also be used for other conditions as determined by your doctor.

Muromonab-CD3 is an immunosuppressant. It blocks the action of certain blood cells (eg, T lymphocytes) that can cause the body to reject the transplanted organ.

Do NOT use muromonab-CD3 if:

  • you are allergic to any ingredient in muromonab-CD3 or to products made with mouse protein
  • you have certain levels (greater than or equal to 1:1000) of antimouse antibody titers
  • if you are pregnant, suspect that you may be pregnant, or are breast-feeding
  • you have uncompensated heart failure, fluid overload, uncontrolled high blood pressure, or a history of seizures, or you are at risk for seizures
  • you have a fever higher than 100 degrees F (37.8 degrees C), chickenpox, or shingles

Contact your doctor or health care provider immediately if any of these apply to you.

Before using muromonab-CD3:

Some medical conditions may interact with muromonab-CD3. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have heart problems (eg, angina, heart failure), lung problems (eg, fluid buildup, chronic obstructive pulmonary disease), nervous system problems, or shock due to a severe infection (sepsis)
  • if you have a fever or infection, swelling, high or low blood electrolyte levels (eg, potassium, sodium), or conditions that may increase or decrease the amount of fluid in the body (eg, dialysis, dehydration, blood loss)
  • if you have history of seizures, blood clots or blood clotting problems, blood vessel problems, stroke, or recent heart attack or head injury

Some MEDICINES MAY INTERACT with muromonab-CD3. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Diuretics (eg, furosemide, hydrochlorothiazide) because they may increase the risk of muromonab-CD3s side effects

This may not be a complete list of all interactions that may occur. Ask your health care provider if muromonab-CD3 may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use muromonab-CD3:

Use muromonab-CD3 as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Muromonab-CD3 will be given as an injection at your doctor's office, hospital, or clinic.
  • If you miss a dose of muromonab-CD3, contact your doctor right away.

Ask your health care provider any questions you may have about the proper use of muromonab-CD3.

Important safety information:

  • Muromonab-CD3 may cause dizziness or drowsiness. These effects may be worse if you take it with alcohol or certain medicines. Use muromonab-CD3 with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Muromonab-CD3 may lower the ability of your body to fight infection. Avoid contact with people who have colds or infections. Tell your doctor if you notice signs of infection like fever, sore throat, rash, or chills.
  • Muromonab-CD3 may increase your risk of developing certain cancers (eg, lymphoma). Contact your doctor if you experience any unusual lumps or skin thickening, growths, or color changes. Discuss any questions or concerns with your doctor.
  • Lab tests, including kidney and liver function, blood pressure, blood counts, blood electrolytes, weight checks, and chest x-rays, may be performed while you use muromonab-CD3. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
  • Use muromonab-CD3 with caution in the ELDERLY; they may be more sensitive to its effects.
  • Muromonab-CD3 should be used with extreme caution in CHILDREN; they may be more sensitive to its effects, including bleeding or swelling in the brain, seizures, meningitis, certain infections, blood clots, dehydration, and the development of certain cancers (eg, lymphoma).
  • PREGNANCY and BREAST-FEEDING: It is not known if muromonab-CD3 can cause harm to the fetus. Do not use muromonab-CD3 if you are pregnant. If you think you may be pregnant, contact your doctor right away. It is not known if this medicine is found in breast milk. Do not breast-feed while taking muromonab-CD3.

Possible side effects of muromonab-CD3:

Every medicine can cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Decreased appetite; diarrhea; dizziness; fatigue; flushing; headache; increased sweating; nausea; nervousness; tiredness or weakness; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); black or tarry stools; calf pain/tenderness; chest pain; confusion; decreased hearing/deafness; decreased urination; fainting; fast, slow, or irregular heartbeat; fever; hallucinations; hoarseness; mental or mood changes; muscle or joint aches or pain; neck soreness or stiffness; numbness of an arm or leg; one-sided weakness; paralysis; seizures; severe or persistent tiredness, weakness, nausea, vomiting, or diarrhea; shortness of breath; signs of infection (eg, chills, fever, sore throat); skin thickening, growths, or color change; speech changes; stomach pain; sudden severe dizziness or headache; swelling of the arms, legs, hands, or feet; tremor; trouble swallowing; uncontrolled muscle movements; unusual bruising or bleeding; unusual lumps; vision changes (eg, blindness, sensitivity to light); wheezing.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include decreased urination; diarrhea; fever; muscle pain; severe chills; shortness of breath; swelling; or vomiting.

Proper storage of muromonab-CD3:

Muromonab-CD3 is usually handled and stored by a health care provider. If you are using muromonab-CD3 at home, store muromonab-CD3 as directed by your pharmacist or health care provider. Keep muromonab-CD3 out of the reach of children and away from pets

General information:

  • If you have any questions about muromonab-CD3, please talk with your doctor, pharmacist, or other health care provider.
  • Muromonab-CD3 is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take muromonab-CD3 or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about muromonab-CD3. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to muromonab-CD3. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using muromonab-CD3.

Issue Date: June 3, 2015

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.