Botulinum toxin therapy in pain management.

BTs seem to be a useful treatment in refractory MPS and headache. Presumably BTs work by breaking the spasm or pain cycle giving the patient a "window of opportunity" for traditional conservative measures to have a greater beneficial impact, but several studies suggest that a direct antinociceptive effect distinct from any reduction in muscle spasm may be at play. The major benefit of BTs compared with standard therapies is duration of response. We do not advocate that BTs be used as a first line treatment for MPS or headache. However, in refractory cases where nothing else has worked, it may offer a chance for improvement or cure not otherwise available. For now, it remains an off label, but increasingly accepted, approach in-patients with refractory myofascial pain and headache, who despite multidisciplinary approaches, continue to suffer.