Mitoxantrone injection is used to adults with various forms of multiple sclerosis (MS; a disease in which the nerves do not function properly and people may experience weakness, numbness, loss of muscle coordination, and problems with vision, speech, and bladder control) including the following:

relapsing-remitting forms (course of disease where symptoms flare up from time to time), or
progressive relapsing (course of disease with occasional relapses), or
secondary progressive forms (course of disease where relapses occur more often).

Mitoxantrone injection is also used together with steroid medications to relieve pain in people with advanced prostate cancer who did not respond to other medications. Mitoxantrone injection is also used with other medications to treat certain types of leukemia. Mitoxantrone injection is in a class of medications called anthracenediones