Treatment of Idiopathic Gastroparesis With Injection of Botulinum Toxin Into The Pyloric Sphincter Muscle

We aimed to determine if botulinum toxin injection into the pyloric sphincter improves gastric emptying and reduces symptoms in patients with idiopathic gastroparesis. Patients with idiopathic gastroparesis not responding to prokinetic therapy underwent botulinum toxin (80–100 U, 20 U/ml) injection into the pyloric sphincter. Gastric emptying scintigraphy was performed before and 4 wk after treatment. Total symptom scores were obtained from the sum of eight upper GI symptoms graded on a scale from 0 (none) to 4 (extreme). Ten patients were entered into the study. The mean percentage of solid gastric retention at 4 h improved from 27 ± 6% (normal < 10%) before botulinum toxin injection into the pylorus to 14 ± 4% (p = 0.038) 4 wk after treatment. The symptom score decreased from 15.3 ± 1.7 at baseline to 9.0 ± 1.9 (p = 0.006) at 4 wk, a 38 ± 9% decrease. Improvement in symptoms tended to correlate with improved gastric emptying of solids (r = 0.565, p = 0.086). This initial pilot study suggests that botulinum toxin injection into the pylorus in patients with idiopathic gastroparesis improves both gastric emptying and symptoms.