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Generic name: trimetrexate [ TRY-meh-TREK-sate ]
Brand name: Neutrexin

Trimetrexate must be used with another medicine called leucovorin to protect against potentially serious or life-threatening reactions, such as kidney or liver problems; infected stomach, intestinal or mouth sores; or a decreased ability to fight infections.

Trimetrexate is used for:

Treating moderate to severe Pneumocystis carinii pneumonia (PCP) in patients with weak immune systems, including those with AIDS, who are not able to take the standard treatment. Trimetrexate is used in combination with leucovorin.

Trimetrexate is an anti-infective agent. It works by inhibiting DNA, RNA, and protein synthesis, leading to cell death.

Do NOT use trimetrexate if:

  • you are allergic to any ingredient in trimetrexate, leucovorin, or methotrexate
  • you are taking a nonsteroidal anti-inflammatory drug (NSAID) (eg, ibuprofen) or pristinamycin

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

Before using trimetrexate:

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

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • 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 bone marrow depression, a blood disorder, or kidney or liver problems

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

  • Cisplatin, corticosteroids (eg, prednisone), cyclosporine, etretinate, NSAIDs (eg, ibuprofen), penicillins (eg, amoxicillin), pristinamycin, probenecid, quinolones (eg, ciprofloxacin), salicylates (eg, aspirin), sulfonamides (eg, sulfamethoxazole), tetracyclines (eg, doxycycline), or trimethoprim because the actions and side effects of trimetrexate may be increased, possibly leading to toxicities
  • Digoxin or hydantoins (eg, phenytoin) because the effectiveness of these medicines may be decreased

This may not be a complete list of all interactions that may occur. Ask your health care provider if trimetrexate 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 trimetrexate:

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

  • Trimetrexate is usually administered as an injection at your doctor's office, hospital, or clinic. If you are using trimetrexate at home, carefully follow the injection procedures taught to you by your health care provider.
  • Trimetrexate should not be given at the same time as fluorouracil. Doses should be separated as directed.
  • If trimetrexate contains particles or is discolored, or if the vial is cracked or damaged in any way, do not use it.
  • Trimetrexate must be used with another medicine, leucovorin, as protection against potentially serious or life-threatening reactions. Treatment with leucovorin must extend 72 hours past the last dose of trimetrexate. Use all leucovorin doses as instructed. If you fail to use the correct dose and all doses of leucovorin, it may cause fatal toxicity.
  • Keep this product, as well as syringes and needles, out of the reach of children and away from pets. Do not reuse needles, syringes, or other materials. Dispose of properly after use. Ask your doctor or pharmacist to explain local regulations for proper disposal.
  • If you miss a dose of trimetrexate, contact your doctor immediately.

Ask your health care provider any questions you may have about how to use trimetrexate.

Important safety information:

  • Do not drink alcohol while you are using trimetrexate.
  • Trimetrexate may reduce the number of clot-forming cells (platelets) in your blood. To prevent bleeding, avoid situations in which bruising or injury may occur. Report any unusual bleeding, bruising, blood in stools, or dark, tarry stools to your doctor.
  • Trimetrexate may lower your body's ability to fight infection. Prevent infection by avoiding contact with people with colds or other infections. Notify your doctor of any signs of infection including fever, sore throat, rashes, or chills.
  • LAB TESTS, including neutrophil counts, platelet counts, liver function, and kidney function, may be performed to monitor your progress or to check for side effects. Be sure to keep all doctor and lab appointments.
  • Use trimetrexate with caution in the ELDERLY because they may be more sensitive to its effects.
  • Trimetrexate is not recommended for use in CHILDREN. Safety and effectiveness have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: Trimetrexate has been shown to cause harm to the fetus. Avoid becoming pregnant while taking trimetrexate. If you think you may be pregnant, discuss with your doctor the benefits and risks of using trimetrexate during pregnancy. It is unknown if trimetrexate is excreted in breast milk. Do not breast-feed while taking trimetrexate.

Possible side effects of trimetrexate:

All medicines may 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:

Confusion; fatigue.

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

Severe allergic reactions (rash; hives; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); chills; drops in counts of blood cells; fever; itching; nausea; sores in mouth; symptoms of a new infection; unusual bruising or bleeding; unusual tiredness or weakness; vomiting; yellow discoloration of skin or eyes.

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 blood disorders.

Proper storage of trimetrexate:

Store trimetrexate at room temperature, between 68 to 77 degrees F (20 to 25 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep trimetrexate out of the reach of children and away from pets.

General information:

  • If you have any questions about trimetrexate, please talk with your doctor, pharmacist, or other health care provider.
  • Trimetrexate 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 trimetrexate 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 trimetrexate. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to trimetrexate. 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 trimetrexate.

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.