Retirees with high prescription drug costs might want to keep an eye on President Trump's hoped-for changes to Medicare. The president's proposed 2020 budget, released Monday, calls for allowing Medicare to negotiate lower prices with pharmaceutical companies and would cap how much beneficiaries pay out-of-pocket under Part D prescription drug coverage, among other provisions. Yet it also would get rid of some help that beneficiaries receive for their medicines. On top of eliminating help with generic drug costs for low-income Medicare recipients, the budget would stop allowing manufacturer discounts to count toward a beneficiary's out-of-pocket costs during the so-called coverage gap under Part D.

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"If those discounts are no longer counted, it means people would spend longer in the coverage gap and spend more out of pocket," said Mary Johnson, Social Security and Medicare policy analyst for The Senior Citizens League. "Those discounts currently are 70 percent of the cost of a drug." Medicare Part D's coverage gap, or "donut hole," is the time between a drug plan's coverage limit ($3,820 for 2019) and the threshold for qualifying for catastrophic coverage ($5,100 for 2019), which is when your share of the cost drops. While Medicare beneficiaries now pay 25 percent for brand-name drugs during that gap — the same share before reaching the drug plan's limit — they also have been able to count manufacturer discounts toward their out-of-pocket costs while in the gap. That helps them reach the catastrophic phase of coverage faster.