injection of botulinum toxin in the treatment of achalasia: a randomized, double blind, controlled clinical trial

our aim was to evaluate the short and long term efficacy of botulinum toxin therapy in iranian patients with achalasia. in a randomized, double blind trial, 20 patients with achalasia, referring to imam khomeini hospital, received either 80 units of botulinum toxin (bt) or placebo (pl) from 1995 to 1998. two weeks later, the response to treatment was assessed on the basis of changes in the symptom score (measured on a scale from o to 9). patients who received pl initially were subsequently treated with bt. after two weeks and six months, assessment was repeated. two weeks after treatment, clinical evaluation revealed that in the bt group all clinical symptoms were improved and the total symptom score had significantly decreased from 6.2±1.4 to 1.9±1.66 (p<0.05) and no significant changes were seen in the clinical score of the pl group. no significant differences were seen in the bt group comparing thoracic pain after the first two weeks. two weeks after the first injection, patients who did not show clinical improvement received toxin with the same previous dose and re-evaluation was performed two weeks after the second injection and six months after the first injection. after six months mean symptom score was 3.4±1.9 (p<0.005) in the bt group and 2.4±1.51 (p<0.005) in the pl group. at this time clinical responses persisted in 12 patients (60%). in conclusion, injection of botulin urn toxin into the lower esophageal sphincter is an effective, safe and simple method of treatment for achalasia, especially in patients who cannot use other methods.