Botulinum toxin for LES spastic disorders

Botulinum toxin is one of the most potent neurotoxins available, blocking vesicular mediated neurotransmitter release from nerve endings and causing a paralysis or reduction in tone of the targeted muscle. Endoscopic injection of botulinum toxin has now been used for achalasia for nearly two decades, with grade I evidence for its efficacy. The experience with other spastic disorders of the esophagus is considerably more limited. Its main advantage is its simplicity and relative safety. On the other hand, its drawbacks include the limited duration of its effects and hence the requirement for repeat injections. Further, it is not very effective in younger patients. While not considered first-line therapy in most patients, it has nevertheless emerged as an alternative therapy for this condition in patients who are considered at high risk for more invasive methods of treatment such as pneumatic dilation or surgery. It is also of some value as a therapeutic trial in patients with equivocal clinical or manometric measures to assess the contribution of lower esophageal tone to symptoms.