This is what people sometimes call the Medicare coverage gap. The donut hole is entered once you and your health plan have reached a pre-set payment total for your prescription drugs. You enter the donut hole once this amount reaches $3,700 in 2017. You might have to pay more for your prescription drugs at this point. You leave the coverage gap once your out-of-pocket costs reach $4,950 for the year; at this point, you reach the catastrophic coverage stage.