What are some situations that necessitate Medicare prior authorization?

Medicare prior authorization is necessary if a drug causes harmful side effects, there are cheaper and better alternative drugs, or the drug is one that people commonly abuse, notes Blue Cross, Blue Shield, Blue Care Network of Michigan. A drug meant for specific diseases also requires Medicare prior authorization.

Medicare prior authorization ensures that a patient receives a medication that suits his health condition, according to Blue Cross, Blue Shield, Blue Care Network of Michigan. Before starting the prior authorization process, a patient or his pharmacist should consult a doctor about the availability of an alternative drug for which prior authorization is not necessary.