Final answer:
The intravenous (IV) route of administration typically lasts the longest for Compazine (Prochlorperazine).
Step-by-step explanation:
The route of administration for Compazine (Prochlorperazine) are intravenous (IV), intramuscular (IM), and oral (PO). Of these routes, intravenous (IV) administration typically lasts the longest. When a drug is administered intravenously, it is directly injected into a vein, allowing for immediate absorption into the bloodstream. As a result, the drug's effects are usually more rapid and longer-lasting compared to other routes of administration.