A few years back I changed jobs; under my previous employer my allergy shots were fully covered under insurance, and I wanted to determine which of my new employer's plans might cover them. At the time I was getting allergy shots on a weekly basis, so if I had to pay it could add up to $80-$100 a month. If "plan A" covered it and cost only $30/month more than "plan B," then it would be worth it to me.

The plan summary from HR didn't say. I called the insurance company, but it was tough to get an answer from their CSRs without being a customer. Finally I got someone sympathetic who gave me their direct line and said if I could get the billing codes, they could run it against the terms of the policies my company negotiated and see what comes up. In the meantime they told me it would cost no more than $25 per injection, which was the limit to "usual customary and reasonable" in my area.

So then I call my allergist's office. They told me I need to speak to their business manager, who only worked 3 days/week, and I of course called on one of those other two days. When I called back, she categorically refused to give me the billing code they'd use. I asked her to clarify whether she was unable to give me the code or if she was choosing not to do so, and she responded that it was the latter.

So basically I just had to wing it and choose a plan. And a new allergist.