Dimethyl fumarate is an anti-inflammatory. it is indicated for multiple sclerosis patients with relapsing forms and is also being investigated for the treatment of psoriasis. the mechanism of action of dimethyl fumarate in multiple sclerosis is not well understood.dose:starting dose: 120 mg twice a day, orally, for 7 days.maintenance dose after 7 days: 240 mg twice a day, orally.