If you decide not to get it when you’re first eligible, and you don’t have other creditable prescription drug coverage (like drug coverage from an employer or union) or get Extra Help, you’ll likely pay a late enrollment penalty if you join a plan later. Generally, you’ll pay this penalty for as long as you have Medicare drug coverage. To get Medicare drug coverage, you must join a Medicare-approved plan that offers drug coverage. Each plan can vary in cost and specific drugs covered.