A team from Sweden and Australia assessed the effect of baclofen on transient lower esophageal sphincter relaxations (TLESRs) and postprandial gastroesophageal reflux in patients with reflux disease.
TLESRs are the major cause of gastroesophageal reflux in normal subjects and in most patients with reflux disease.
The gamma aminobutyric acid (GABA) receptor type B agonist, baclofen, is a potent inhibitor of TLESRs in normal subjects.
In 20 patients with reflux disease, esophageal motility and pH were measured, with patients in the sitting position. This was done for 3 hours after a 3000 kJ mixed nutrient meal.
|Effects of baclofen:|
- Reduced TLESR rate by 40%
- Reduced reflux episode rate by 43%
On separate days, at least one week apart, 40 mg oral baclofen or placebo was given 90 minutes before the meal.
Baclofen reduced the rate of TLESRs by 40%, from a median of 15 to 9 per three hours, and increased basal lower esophageal sphincter pressure.
The investigators found that baclofen also significantly reduced the rate of reflux episodes by 43%, from 7.0 to 4.0 per three hours.
However, baclofen had no effect on esophageal acid exposure (baclofen 4.9% vs placebo 5.0%).
Dr Q. Zhang, of the Royal Adelaide Hospital, Australia, said on behalf of colleagues, "In patients with reflux disease, the GABAB agonist baclofen significantly inhibits gastroesophageal reflux episodes by inhibition of TLESRs.
"These findings suggest that GABAB agonists may be useful as therapeutic agents for the management of reflux disease," it was concluded.