Which type of prescription drug coverage is limited under Medicare?

The correct choice indicates that Medicare does not provide coverage for medicines administered in a hospital outpatient department. This is because outpatient drugs are often considered part of the services provided during that outpatient visit, and patients typically need to pay for those medications separately. Medicare Part D, which covers prescription drugs, applies mainly to medications that are filled at a pharmacy rather than those administered in a hospital or outpatient setting.

Medicare generally covers outpatient prescription drugs that patients can obtain through their pharmacy, but certain medications given directly in a healthcare facility, such as those given intravenously or through injections during outpatient treatments, fall outside the scope of typical Medicare Part D coverage. Hence, this demonstrates a limitation in prescription drug coverage under Medicare.

The other options reference types of medications or settings that may be covered by various parts of Medicare or not specifically limited in the same way. For instance, over-the-counter medications are not covered by Medicare, but oral medications prescribed by any healthcare provider, including specialists, and generally covered when they are part of a Medicare plan.