The effects of amantadine and pemoline on cognitive functioning in multiple sclerosis
M. W. Geisler, M. Sliwinski, P. K. Coyle, D. M. Masur, C. Doscher and L. B. Krupp
Department of Neurology, State University of New York at Stony Brook, USA.
BACKGROUND: Amantadine hydrochloride and pemoline, both frequently used to
treat the fatigue of multiple sclerosis (MS), may also improve attention
and other cognitive functions in MS. To our knowledge, these agents have
never been compared in a placebo-controlled trial of patients with MS.
OBJECTIVE: To evaluate the effects of amantadine and pemoline on cognitive
functioning in MS. METHODS: A total of 45 ambulatory patients with MS and
severe fatigue were treated for 6 weeks with amantadine, pemoline, or
placebo using a parallel group design. They underwent comprehensive
neuropsychological testing to determine treatment effects on cognitive
functioning. Primary outcome measures were tests of attention (Digit Span,
Trail Making Test, and Symbol Digit Modalities Test), verbal memory
(Selective Reminding Test), nonverbal memory (Benton Visual Retention
Test), and motor speed (Finger Tapping Test). RESULTS: Fatigue did not
significantly correlate with any of the neuropsychological outcome measures
at baseline or after treatment. All three treatment groups improved on
tests of attention (P < .003), verbal memory (P < .001), and motor
speed (P < .002). There were no significant differences between
amantadine, pemoline, and placebo. CONCLUSIONS: Cognitive functioning in MS
is independent of fatigue. Neither amantadine nor pemoline enhances
cognitive performance in MS compared with placebo.