Here we report the case of a 44-year old patient with a progressive MS whose upper limb tremor was markedly reduced under treatment with 4-aminopyridine, as documented in a Tremor Activities of Daily Living questionnaire and in the 9-Hole Peg test. Hand accelerations decreased in the left hand from 10.9 m/sec2 to 2.2 m/sec2 and in the right hand from 4.2 m/sec2 to 0.9 m/sec(2). This case report indicates for the first time that 4-aminopyridine might be effective in the symptomatic treatment of tremor entities in patients with MS. The finding calls for further prospective studies to determine the usefulness of 4-aminopyridine or its sustained-release form dalfampridine in treating patients with tremor and MS.
