Methotrexate (Rheumatrex) High Dose Special Investigation (Regulatory Post Marketing Commitment Plan)

Methotrexate should be administered at the weekly dose of 6 mg orally once a week or twice or three times a week by subdividing the weekly dose into the relevant number of portions. When administering the subdivided doses, MTX should be administered at the interval of 12 hours on Day 1 to Day 2. When the weekly dose is subdivided into two portions, suspend the administration for the remaining 6 days. When the weekly dose is subdivided into three portions, suspend the administration on the remaining 5 days. Repeat this weekly cycle. The dose should be adjusted as appropriate depending on the age, symptom, tolerability, and response to the MTX Preparation in individual patients. The weekly dose should not be higher than 16 mg.