A double-blind, randomized, crossover trial of pemoline in fatigue associated with multiple sclerosis

Fatigue occurs in a majority of patients with MS and is generally independent of measurable neurologic disability. Few options for treatment are available. We conducted a double–blind, placebo–controlled, crossover trial for each of two 4–week treatment periods. Forty–six eligible patients entered and five dropped out due to concurrent exacerbations. Nineteen patients (46.3%) experienced excellent or good relief of fatigue with pemoline, and eight patients (19.5%) with placebo (p = 0.06, Fisher's exact test). One–fourth of patients did not tolerate the drug well, and 7% had to discontinue pemoline during the study due to side effects. The most common side effects were anorexia, irritability, and insomnia. Pemoline may be an effective short–term treatment for fatigue associated with MS, but its adverse effects are not well tolerated by many patients.