The “Poison Chair” Treatment for Multiple Sclerosis

In the very curious incident of the “poison chair,” hundreds of people in several European cities appeared at clinics with eczematous burns that had no apparent cause. The source was found to be dimethyl fumarate (fumarate), which was used as a fungicide and desiccant in the shipping of sofas. A Finnish physician uncovered the toxin by doggedly pursuing a local outbreak.1 Fumarate and its esters have had a much better safety record as medicinal than as industrial agents. A German biochemist administered fumaric acid to himself in 1959, believing his psoriasis was due to a deficiency of fumarate,2 and a . . .