Methotrexate is used to treat cancer. This drug is given in the vein (IV).
Changes in lung function. You may have a dry cough or trouble breathing.
Severe bone marrow depression, which is a decrease in the number of white blood cells, red blood cells, and platelets, which can very rarely be life-threatening. This may raise your risk of infection, make you tired and weak (fatigue), and raise your risk of bleeding.
Severe diarrhea and inflammation (swelling) of your intestines, or stomach may occur, which can very rarely be life-threatening.
This drug may raise your risk of getting a second cancer such as lymphoma.
Inflammation (swelling) of your lungs, which can very rarely be life-threatening.
Tumor lysis syndrome may occur as a result of this drug acting on the cancer cells very quickly. This may affect how your kidneys work.
Increased risk of infection, which may very rarely be life-threatening.
Changes in your central nervous system can happen. The central nervous system is made up of your brain and spinal cord. You could feel extreme tiredness, agitation, confusion, hallucinations (see or hear things that are not there), trouble understanding or speaking, loss of control of your bowels or bladder, eyesight changes, numbness or lack of strength to your arms, legs, face, or body, and coma. If you start to have any of these symptoms call your doctor right away.
Severe allergic skin reaction, which may very rarely be life-threatening. You may develop blisters on your skin that are filled with fluid or a severe red rash all over your body that may be painful.
Talk to your doctor before receiving any vaccinations during your treatment. Some vaccinations are not recommended while receiving methotrexate.
If you are getting this drug by injection into the fluid that surrounds the brain and spinal cord (intrathecal), your side effects might be different than those listed above. Please talk to your doctor about these side effects.
These side effects may be more severe if you are receiving high doses of this medication. When receiving high doses of methotrexate, you may also receive a medication called leucovorin, which helps decrease the side effects of methotrexate. Please follow the administration instructions from your medical team very closely.
Drink plenty of fluids (a minimum of eight glasses per day is recommended). This is very important if you are receiving high doses of methotrexate.
There are no known interactions of methotrexate with food.
Folic acid supplements may interfere with how methotrexate works. Avoid use of folic acid supplements while taking this drug. Folic acid may be in your multivitamin.
This drug may also interact with other medicines. Tell your doctor and pharmacist about all the medicines and dietary supplements (vitamins, minerals, herbs and others) that you are taking at this time. The safety and use of dietary supplements and alternative diets are often not known. Using these might affect your cancer or interfere with your treatment. Until more is known, you should not use dietary supplements or alternative diets without your cancer doctor's help.
Drugs that treat heartburn and stomach upset such Protonix®, Nexium®, Prilosec®, Pepcid®, Tagamet®, and Zantac® may interact with methotrexate and cause serious harm. Call your doctor to find out what drug you may take to help with heartburn or stomach upset.
Non-steroidal anti-inflammatory drugs (NSAIDs) – e.g., ibuprofen and naproxen and salicylates e.g., aspirin, can interact with methotrexate and cause serious harm, or fatality. Avoid the use of these drugs with methotrexate.
Do not drink alcohol while taking this medicine. Alcohol may increase your risk of changes in your liver function.
Pregnancy warning: This drug can have harmful effects on the unborn baby. Women of child bearing potential should use effective methods of birth control during your cancer treatment and for at least one ovulatory cycle after treatment. Men with female partners of child bearing potential should use effective methods of birth control during your cancer treatment and for at least 3 months after your cancer treatment. Let your doctor know right away if you think you may be pregnant (or may have impregnated your partner).
Breastfeeding warning: Women should not breast feed during treatment because this drug can enter the breast milk and cause harm to a breast feeding baby.