Get emergency medical help if you have signs of an allergic reaction to methotrexate: (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning in your eyes, skin pain, red or purple skin rash that spreads and causes blistering and peeling).
Methotrexate can cause serious or fatal side effects. Call your doctor at once if you have:
sudden chest pain, wheezing, dry cough, cough with mucus, chest pain, feeling short of breath;
fever, chills, swollen lymph glands, night sweats, weight loss;
blisters or ulcers in your mouth, red or swollen gums, trouble swallowing;
vomiting, diarrhea, blood in your urine or stools;
skin changes such as redness, warmth, swelling, or oozing;
low blood cell counts - fever, chills, tiredness, mouth sores, skin sores, easy bruising, unusual bleeding, pale skin, cold hands and feet, feeling light-headed or short of breath;
kidney problems - little or no urination, swelling in your feet or ankles;
liver problems - swelling around your midsection, right-sided upper stomach pain, nausea, loss of appetite, dark urine, jaundice (yellowing of the skin or eyes);
nerve problems - confusion, weakness, drowsiness, coordination problems, feeling irritable, headache, neck stiffness, vision problems, loss of movement in any part of your body, seizure; or
signs of tumor cell breakdown - tiredness, weakness, muscle cramps, nausea, vomiting, diarrhea, fast or slow heart rate, tingling in your hands and feet or around your mouth.
Common methotrexate side effects may include:
fever, chills, tiredness, not feeling well;
low blood cell counts;
mouth sores;
nausea, stomach pain;
abnormal liver function tests;
hair loss;
burning skin lesions; or
being more sensitive to light.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
 Methotrexate side effects (more detail)
