Can Botulinum Toxin Improve Disabling Tremor Caused by Multiple Sclerosis?

Tremor can be a disabling and frustrating symptom in multiple sclerosis (MS). No treatment with a lasting and consistent functional benefit has been identified, despite much research. Now, investigators have tested the effect of botulinum toxin (BT) in 23 people with mostly moderate, upper-extremity tremor of posture, action, and intentional movement caused by MS, in a randomized, double-blind, crossover trial. Participants received BT injections directed toward agonist and antagonist muscles related to specific tremor patterns.

At baseline, participants had good proximal and distal upper-limb strength (median Medical Council Rating, 5; interquartile range, 4.5–5.0) and high Expanded Disability Status Scale scores (median, 5.5; interquartile…