Which statement correctly classifies Esomeprazole (Nexium)?

Esomeprazole (Nexium) is correctly classified as a proton pump inhibitor (PPI). It functions by irreversibly inhibiting the H+/K+ ATPase enzyme in the gastric parietal cells, which is crucial for the secretion of gastric acid. By blocking this enzyme, esomeprazole significantly reduces the amount of acid produced in the stomach, leading to a decrease in gastric acidity. This mechanism is particularly beneficial for treating conditions such as gastroesophageal reflux disease (GERD) and peptic ulcers.

Proton pump inhibitors like esomeprazole are distinct from antacids, which neutralize existing stomach acid rather than preventing its production. Prokinetic agents, on the other hand, enhance gastrointestinal motility and are used to treat conditions involving delayed gastric emptying, while antihistamines mainly act on histamine receptors and are not directly involved in regulating stomach acid production.

Thus, the classification of esomeprazole as a proton pump inhibitor is based on its specific role in inhibiting gastric acid secretion, making it effective in managing acid-related disorders.