Indications and efficacy of botulinum toxin in disorders of the gastrointestinal tract.

In recent years, botulinum toxin type A (BT) has been found to be effective in the treatment of various spastic disorders of smooth muscle in the upper and lower gastrointestinal tract. The short-term efficacy of intrasphincteric injection of BT in achalasia is now well established, however, because of the chronic nature of the disease, patients will require repeated injections at regular intervals. In contrast, after a single injection into the anal sphincter, BT has impressively high healing rate with minimal side effects. BT remains a novel therapeutic approach in a range of other gastrointestinal motility disorders including diffuse oesophageal spasm, sphincter of Oddi dysfunction and anismus, and the list of its indications is increasing. BT seems to be safe but as its long-term effects remain unestablished, it should be used with caution in younger patients. In this review we discuss the mechanism of action, indications, efficacy and side-effects of BT with its use in various areas of gastrointestinal tract.