Immunosuppressive drugs: azathioprine in the treatment of myasthenia gravis.

Azathioprine may be tried for treatment of severe myasthenia gravis, in a dose of 2 mg/kg BW. With careful monitoring the side reactions may be controlled. The therapeutic response will occur after a time delay of 4-8 months. About one-third of patients with type II MG (severe, late onset, HLA B8-) will proceed to a complete but azathioprine-dependent remission, and the remaining two-thirds to a marked improvement. In type I MG (early onset, HLA B8+) azathioprine is less effective but will help keep down the need for corticosteroids or plasmapheresis.