MTX, which stands for methotrexate, is an anti-cancer drug as well as a drug that regulates immune function. It is mainly used in the treatment of many types of cancer, like leukemia, lymphoma, head and neck cancer, lung cancer, etc. It can also be used to treat psoriasis. However, this drug may cause fetal death or congenital malformation, so it is prohibited for pregnant women. If used for a long time, it may produce hepatotoxicity, the main manifestation of which is liver fibrosis and cirrhosis. Therefore, if you need to use the drug for a long time, you must return to the hospital for regular checkups, and some patients may also need to have this liver biopsy. Methotrexate can cause some serious side effects, such as lung disease, as well as tumor lysis syndrome, severe fatal infections, gastrointestinal reactions and severe skin reactions, so the drug must be taken under the guidance of a doctor, and the process of taking it must be monitored more closely, not to take the drug on your own.