Medicare is complicated. Medicare is constantly changing. Changes are usually small but can have a big impact. Some changes are great such as the gradual closing of the doughnut hole because of the Affordable Care Act (aka Obamacare). Some changes aren't really changes, they are just sudden enforcements of existing law. Nonetheless, these changes are confounding. One example is the current Medicare push to enforce drug denials for "off label" drug usage. There are no easy ways to find out about policy changes. AARP sometimes will highlight a change in their publications. But, typically Medicare recipients don't find out about them until they encounter the situation.
I volunteer on a help line at a non-profit organization called the Medicare Rights Center (http://www.medicarerights.org/). Recently, there have been a number of calls regarding the "off label" denial issue. My normal inclination is to suspect the insurance companies. However, in this case it is the Medicare administrative arm - CMS that issued instructions to insurance companies to do the denials. When part D legislation was passed into law in 2003, the insurance rules for drug coverage stipulated drugs are covered only for FDA approved conditions. The reason Medicare cares about what is covered is because Medicare subsidizes the insurance companies. For example, there is a pain alleviation drug called Lidocaine and it comes in patch form. It was approved in 1999 by the FDA to treat pain associated with shingles. However, doctors often prescribe it to help with muscle pain. That's an off label use. A woman called who had been using the patch for five years for back pain. Suddenly, her part D plan denied coverage.
There was no explanation in the denial notice about why this drug was suddenly denied beyond "not medically necessary". There is also no point in appealing the denial (unless the off label use is related to a cancer treatment - then Medicare is more flexible) since it is Medicare enforcing the off label restrictions - not the insurance companies. If you want more information about off label drug use rules in Medicare here is a link:
Unfortunately, doctors are as clueless as patients about an enforcement until they encounter it. Sometimes there are workarounds. For example, if you use a doctor that does not accept Medicare and that doctor orders a lab test at a lab that will accept Medicare, the test will not be covered by your Medicare insurance because the origin was from a non-participating doctor. The enforcement of this rule started a couple of years ago. Non-participating doctors now work with doctors who do accept Medicare to ask them to submit lab tests so that it will be covered. It's crazy to me to force people to only go to Medicare doctors for everything but that's how the law was designed.
The Medicare Rights Center has a great information data base you can search at http://www.medicareinteractive.org/ but it is unlikely you will find this type of information. I suggest when you encounter a baffling denial, call the Medicare Rights Center (1-800-333-4114) because they will know what is trending. They also have a great subscription (free) newsletter that often highlights these trends.
Of course, you can also always call 1-800-MEDICARE to ask questions. Did you know --- the Medicare helpline is available 24 hours a day, 7 days a week? The best time to call is late at night or early in the morning. I suggest you use the rule of 3 when you call Medicare. What is the rule of 3? Call 3 different times to ask the same question. Medicare call center agents highly vary in capability. It's not as bad as OneX. I am not sure that's a compliment.
Finally, if you think the Medicare "rule" is unfair, complain to your congressional representative. Tell them, if the rule is so great, why aren't they required to use Medicare when they retire from congress. Retired congressional representatives get federal health insurance coverage for life if they have been in congress at least five years. That's actually less then the eligibility for Medicare, which requires 10 years of work. Also, support AARP. It is a powerful resource as a Medicare lobby organization.