Should I choose a Medicare plan based mostly on my prescriptions?

Prescriptions matter a lot, and too many people overlook them when picking a plan. Medicare drug coverage, called Part D, is either built into a Medicare Advantage plan or purchased separately as a standalone plan alongside Original Medicare. Either way, every plan has its own list of covered drugs called a formulary, and the costs for the same medication can be dramatically different from one plan to the next.So yes, you should absolutely run your specific prescriptions through each plan you're considering before you enroll. Medicare.gov has a free tool that lets you compare drug costs across plans using your actual medications and dosages. This step alone can save people hundreds of dollars a year.That said, prescriptions are not the only thing that matters. A plan with great drug coverage might have a narrow network that doesn't include your primary doctor or a specialist you rely on. It might have high copays for hospital stays or specialist visits. It might require prior authorization (meaning the plan has to approve certain treatments before they're covered) for things you use regularly.Think of drug costs as one leg of a three-legged stool. The other two are your medical care costs and your access to the providers you trust. All three need to hold up or the whole thing tips over.