Medicare’s donut hole is the bane of existence for retirees with expensive medications. They will get substantial relief in 2025, when the Inflation Reduction Act, signed by President Biden last week, will cap all retirees’ annual drug copayments at $2,000. Monthly drug plan premiums are not included in this cap. The cap will effectively eliminate the donut hole that currently requires retirees to pay 25 percent of the cost of their prescription drugs until they reach a threshold amount. The threshold increases every year and hit $7,050 this year. A relatively small group of about 1.5 million retirees pay more than $2,000 for their prescriptions. But many of them are spending $5,000, $10,000 or more. “It’s going to be an…