Side effects of methotrexate
The most commonly observed adverse events (AEs) of low-dose methotrexate therapy are associated with the gastrointestinal tract, including:
- and less often stomatitis or diarrhea.
More serious AEs include
- bone marrow suppression
- 43 and rarely hyper-sensitivity pneumonitis
- opportunistic infections
Due to these potentially severe side effects, a specific evaluation is recommended for patients before the start of methotrexate. Methotrexate is a known teratogen and is contraindicated in pregnancy.
Patients should get x rays done to rule out lung injury, CBC, CMP and pregnancy test.
The dose is 12.5 mg methotrexate orally once a week with 1 mg folic acid.