If I meet the DSM diagnostic criteria, and the prior authorization for a drug just says that I must be "diagnosed with" the condition, would my insurance company require any other documentation of testing to prove the diagnosis?

First of all, please forgive my ignorance. I’m a Canadian living in America and walking into a completely different insurance/healthcare setup is so overwhelming. I have coverage through BCBS Illinois.

I’m currently seeking a diagnosis for narcolepsy. The most common way to be diagnosed is through a MSLT test, in which you are given a few opportunities to nap and if you fall asleep within a certain amount of time each nap and go into REM, you get diagnosed. I had a MSLT done, but it was negative. Two different neurologists that I’ve seen think it was a false negative, because I had extremely bad sciatica and anxiety that day.

Anyway, technically the DSM 5 says you can be diagnosed with Narcolepsy Type 1 (with cataplexy) if you have a strong enough history of cataplexy, which I do (I used to full on collapse when laughing, and now have extreme leg weakness when extremely upset or elated). I meet all other symptom based criteria for narcolepsy.

The prior authorization requirement for one of the drugs for narcolepsy seems to vary based on state. For example, in some states, BCBS requires a positive MSLT, along with the diagnosis. I found this out by finding the PDF forms online from the BCBS documentation. The form for BCBS IL, however, just requires that I have a diagnosis of narcolepsy with cataplexy.

So if I’m diagnosed based on the criteria, and the prior auth doesn’t mention any specific criteria, is it possible that it would be approved or is there some other avenue through which BCBS IL would require the MSLT to be positive? For example would they require the positive MSLT just to acknowledge the Narcolepsy diagnosis or something?