Botulinum toxin a shot in the arm for preventing multiple sclerosis tremor

"Treatments in use for tremor in MS are not sufficiently effective and new alternatives are needed," said study author Anneke van der Walt, MD, consultant neurologist at The Royal Melbourne Hospital and research fellow with the University of Melbourne in Australia.

For the study 23 people with MS were given botulinum toxin type A injections or a saline placebo for three months. Then they received the opposite treatment for the next three months. Scientists measured the tremor severity and their ability to write and draw before, during and after receiving the treatments. Video assessments were also taken every six weeks for six months.

The study found that people saw significant improvement in tremor severity, writing and drawing at six weeks and three months after the botulinum toxin treatment compared to after placebo. In tremor severity, the participants improved an average of two points on a 10-point scale, bringing their tremor from moderate to mild. In writing and drawing, participants improved by an average of one point on a 10-point scale.

"Our study suggests a new way to approach arm tremor related to MS where there are currently major treatment challenges and it also sets the framework for larger studies," said van der Walt.

Muscle weakness developed in 42 percent of people after treatment with botulinum toxin compared to six percent after placebo. The weakness was generally mild and went away within two weeks.

The study was supported by the Box Hill MS Research Fund and The Royal Melbourne Hospital Neuroscience Foundation.