GERD — esomeprazole
Gastrooesophageal reflux disease (GERD), often referred to as heartburn, is the result of the reflux of the gastric contents into the oesophagus. In the past, treatment was symptomatic, and limited to the neutralisation of the gastric acid with antacids. An advance was made with the introduction of the histamine H2-receptor antagonists, which limited the production of gastric acid, but at a late stage. Later, the treatment of GERD was improved by the development of the proton pump inhibitors, of which omeprazole was the first. Several others are now available, such as lansoprazole, pantoprazole and rabeprazole.
Such drugs act at an early stage of gastric acid formation, and are free from some of the side-effects of older compounds. Response, however, may be variable, and in view of the nature of GERD, a drug with a more extended and reliable action would have clinical and social advantages.
It has long been known that some active compounds are chiral in nature, and that one isomer may be more active than another. Attention has been turned accordingly to the potential of the optical isomers of omeprazole, with particular reference to the S-isomer, identified as esomeprazole.1
This isomer has since been studied for the treatment of GERD in many centres, and a report by Richter is of interest as it compares the response to esomeprazole in doses of 40mg with that following omeprazole in doses of 80mg.2
The response, as indicated by the relief of heartburn and the reduction of regurgitation showed that esomeprazole brought about considerable clinical improvement after four weeks' treatment, compared with the eight weeks required with omeprazole, and that the results were consistent with varying symptomatic severity. Higher doses were not associated with any improved benefit, but indicated that for extended treatment over some months esomeprazole given every third day gave adequate symptomatic control. Essentially similar results have been reported by other workers.3
It is well known that GERD relapse may be a result of the presence of Helicobacter pylori, and combined treatment with esomeprazole and suitable antibiotic therapy in such cases may not only promote healing but may also prevent subsequent relapse.