What is the term for the portion of prescription drug costs a Medicare patient must pay out of pocket?

The term "donut hole" refers to a specific coverage gap in Medicare Part D prescription drug plans. After a Medicare beneficiary has spent a certain amount on covered drugs, they enter this coverage gap where they are responsible for a larger portion of drug costs, up to a specified limit. This gap can lead to a significant out-of-pocket expense for beneficiaries until they reach a threshold that qualifies them for catastrophic coverage, at which point their costs are significantly reduced again.

The other terms listed, while related to healthcare costs, have different meanings. For instance, a co-payment is a fixed amount that a patient pays for a specific service or prescription at the time of service. A deductible refers to the amount that a person must pay out of pocket before their insurance begins to cover costs. Out-of-pocket expenses could refer to any medical costs that a patient must pay themselves, but they do not specifically define the Medicare Part D coverage gap that the term "donut hole" does. Thus, "donut hole" is the most accurate term for describing that particular situation in Medicare prescription coverage.