You don't say why you had to come off it.when the rash that I get with methotrexate gets too bad I take a reduced amount but as Mrs Mop has said, two weeks without it and you can usually feel everything start to sieze up! Methotrexate can cause abnormal liver function. It's important to routinely have your blood tested for liver function so your doctor can monitor you for unwanted side effects. Other than abnormalities with liver function, the most common side effects associated with methotrexate are nausea and vomiting. Methotrexate can cause serious or life-threatening side effects. Tell your doctor if you have diarrhea , mouth sores, cough, shortness of breath, upper stomach pain, dark urine, numbness or tingling, muscle weakness, confusion, seizure, or skin rash that spreads and causes blistering and peeling. Methotrexate is a powerful medication that can be used for many serious conditions. MTX is an antineoplastic (anticancer) drug that is used in protocols to treat all kinds of cancers such as leukemias, lymphomas, and breast cancers. Methotrexate is a potent drug with many side effects. Even those on low doses normally report adverse reactions, often very unpleasant and adding to their other health problems rather than clearing them up. Methotrexate is used to treat severe psoriasis (a skin disease in which red, scaly patches form on some areas of the body) that cannot be controlled by other treatments. ** Originally posted by mariaoneill ** Ilene, I think you and I must have started the injections about the same time. I inject on Wednesdays and notice a lot of fatigue beginning Monday afternoon and I drag until Wednesday night. The Oxford Journal of Medicine reports, After administration, methotrexate is widely distributed in body tissues, the highest concentrations being in the kidneys, gallbladder, spleen, liver and skin. Methotrexate is a chemotherapy drug that prevents cell reproduction by interfering with folic acid activation.It is very effective, but it can cause side effects like nausea, mouth ulcers, blood problems. Prolonged treatment with MTX may also lead to folic acid deficiency which is why your doctor should also have prescribed Folic acid for you. Methotrexate can sometimes be given along with other drugs to treat your condition. You can usually carry on taking a non-steroidal anti-inflammatory drug (NSAID), such as ibuprofen, or painkillers like paracetamol if needed, unless your doctor advises otherwise.