The present invention is directed to the treatment of multiple sclerosis by periodically
administering a high dose of methotrexate at a level sufficiently high to cross
the blood brain barrier. The methotrexate administration is accompanied by leucovorin
rescue of the periphery. The high dose methotrexate is preferably administered
at 1 to 4 month intervals. The periodic high dose methotrexate treatment may be
used in conjunction with interim treatments using a therapeutic agent that is effective
in treating MS, but does not cross the BBB in cytotoxic amounts. It is contemplated
that the method of the present invention may be employed to treat other non-infectious,
non-neoplastic inflammatory conditions of the CNS.
