Prevention of rejection in renal transplantation
Usually 3 to 5 mg/kg daily at the time of transplant, then 1 to 3 mg/kg daily as maintenance
Active rheumatoid arthritis
Initially about 1 mg/kg daily, increased after 6 to 8 weeks and then at 4-week intervals to a maximum of 2.5 mg/kg daily
Test TPMT and NUDT15 before starting: a deficient patient can be catastrophically myelosuppressed at an ordinary dose