Methotrexate is used when psoriasis involves more than 25 percent of body surface or if it is not responding to topical application (application of creams).u will have to do your blood test like
complete blood count,
liver function test,chest xray before starting it.side effects are there like nausea and changes in your blood parameters , infection.
Next Steps
kindly mention the extent of involvement of your psoriasis
Health Tips
kindly contact dermatologist before starting methotrexate