Submitted by: Clark W. Pinyan, MD, MPH
Edited by: T. Darrell Thomas, MD
Restivo D, et al. Efficacy of Botulinum Toxin A for Treating Cramps in Diabetic Neuropathy. Annals of Neurology
Fifty diabetic patients with diabetic neuropathy and cramps were randomly assigned to two groups. BTX-A (30 or 100 units, depending on site) or saline was injected bilaterally into the gastrocnemius or the small flexor foot muscles. Changes in pain intensity and cramp frequency were evaluated over 20 weeks. Treatment was repeated 5 months after first injection in 19 responders. All outcome measures improved significantly after BTX-A compared with placebo. Improvement began at 1 week post injection and persisted up to week 14. Five of 25 (20%) of patients were non responders. Repeat BTX-A injection produced similar results to the initial administration.
Botulinum toxin injections are already useful in a variety of clinical conditions with cramps and spasms such as multiple sclerosis or lumbar spinal stenosis. This may be an emerging tool in our clinical arsenal in patients who are often refractory to other therapies. This would be contingent on ability to secure reimbursement for these services. Further research may lead to greater acceptance and greater payor approval.