Intrathecal steroids were used in the treatment of 20 patients with multiple sclerosis. This treatment does not appear to affect the incidence of exacerbations of the disease. This treatment does appear to reduce transiently the spasticity and so improve ambulation and bladder control. The mechanism of this effect is not clear but could be due to a local effect of the drug on the lumbosacral roots and consequent alteration of the stretch reflex. Two patients had transient loss of ability to empty the urinary bladder after injection.