Final answer:
The drug that increases gastric emptying is Domperidone. It works as a dopamine receptor antagonist to enhance gastrointestinal motility.
Step-by-step explanation:
The question is asking which drug increases gastric emptying. The correct answer is C. Domperidone. Domperidone is a medication that works as a peripherally selective dopamine D2 and D3 receptor antagonist, which enhances gastrointestinal motility and thereby facilitates gastric emptying. It is often used for its gastroprokinetic properties.
By contrast, A. Omeprazole is a proton pump inhibitor that reduces stomach acid secretion but does not increase gastric emptying. B. Atropine is an anticholinergic that slows gastric emptying. D. Midazolam is a benzodiazepine used primarily for its sedative properties, and E. Prochlorperazine is a dopamine antagonist used as an antiemetic and antipsychotic, which might have effects on gastric motility but is not primarily used to increase emptying.