Wiktionary
esomeprazole
n. A proton pump inhibitor used in the treatment of dyspepsia and similar disorders.
Wikipedia
Esomeprazole
Esomeprazole sold under the brand name Nexium among others, is a proton pump inhibitor which reduces stomach acid. It is used in the treatment of dyspepsia, peptic ulcer disease, gastroesophageal reflux disease, and Zollinger-Ellison syndrome.
It decreases secretion of acid through inhibition of the H/K-ATPase in the parietal cells of the stomach. By inhibiting the functioning of this transporter, the drug prevents formation of stomach acid.
Esomeprazole is the (S)-(−)- enantiomer of omeprazole. Esomeprazole is currently sold over the counter in the US and the UK.