Trimetrexate
Trimetrexate injection
What is trimetrexate injection?
TRIMETREXATE (Neutrexin®) is an antiprotozoal agent. Trimetrexate treats Pneumocystis carinii pneumonia (PCP) in patients who cannot take or have not responded well to more conventional treatments. This infection commonly affects patients whose immune systems are not working properly such as HIV-infected (AIDS) patients. Another medicine called leucovorin must be used at the same time as trimetrexate to help prevent serious side effects. Generic trimetrexate injections are not yet available.
NOTE: This drug is discontinued in the United States.
What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:
blood disorders
dental disease
liver disease
low blood calcium
low blood sodium
recent radiation therapy
an unusual or allergic reaction to trimetrexate, leucovorin, other medicines, foods, dyes, or preservatives
pregnant or trying to get pregnant
breast-feeding
How should I use this medicine?
Trimetrexate is for infusion into a vein.
Trimetrexate is given with another medicine, leucovorin, which prevents some of the serious side effects of trimetrexate. If you are also taking leucovorin, take exactly as directed for the complete length of time prescribed, even if you feel better. It is very important that you complete the full course of treatment and continue to use leucovorin for 3 days after the last dose of trimetrexate. Do not stop taking except on your prescriber's advice.
What if I miss a dose?
If you miss a dose, use it as soon as you can. If it is almost time for your next dose, use only that dose. Do not use double or extra doses.
What drug(s) may interact with trimetrexate?
acetaminophen
bosentan
cimetidine
erythromycin
medicines for fungal infections
Tell your prescriber or health care professional about all other medicines you are taking, including non-prescription medicines, nutritional supplements, or herbal products. Also tell your prescriber or health care professional if you are a frequent user of drinks with caffeine or alcohol, if you smoke, or if you use illegal drugs. These may affect the way your medicine works. Check with your health care professional before stopping or starting any of your medicines.
What should I watch for while taking trimetrexate?
Tell your prescriber or health care professional if your symptoms do not improve.
If you get a fever or sore throat, do not treat yourself. Call your prescriber or health care professional for advice.
What side effects may I notice from receiving trimetrexate?
Side effects that you should report to your prescriber or health care professional as soon as possible:
decreased blood pressure leading to dizziness or lightheadedness
difficulty breathing or shortness of breath
excessive sweating
low blood counts - trimetrexate may decrease the number of white blood cells and platelets in your blood. You may be at increased risk for infections and bleeding (see below)
signs of infection - fever or chills, cough, sore throat, pain or difficulty passing urine
signs of decreased platelets or bleeding - bruising, pinpoint red spots on the skin, black, tarry stools, blood in the urine
skin rash
sores in mouth or throat
Side effects that usually do not require medical attention (report to your prescriber or health care professional if they continue or are bothersome):
chills
diarrhea
nausea, vomiting
Where can I keep my medicine?
This medicine is given in a hospital or clinic setting. You will not store this medicine at home.
Updated:  
March 21, 2017
Sources:  
U.S. FDA-approved Package Insert