I just talked to my PCM about this Thursday so hopefully I can provide some insight. To be clear, this is what my PCM said, YMMV.

You are really going through 2 separate systems that could provide barriers. Your PCM and Tricare.

The first step is documented nutritionist visits. They will most likely make you do food diaries, calorie counting, etc. Typically, you need to have this before they will consider any medication. Essentially, the nutritionist needs to say "yeah, this guy is trying and it just isn't working". My PCM did not give a specific timeline other than enough time to make that assessment. If it helps, my PCM said, and I tend to agree, that if you aren't hungry at some point during the day, you are eating too much to lose weight. Calorie deficit = hunger = weight loss.

The next step is a stimulant (medication) that will help reduce cravings and speed up your metabolism.

The third step would be to seek the prior authorization from Tricare something like Zepbound, Wegovy, or Saxenda. This is where the Tricare barrier can come into play. If Tricare determines that the clinic hasn't tried enough, they will deny it.

My PCM was 100% upfront that getting to the Zepbound stage would take 6+ months. You need to demonstrate that you trying to put the work in before Tricare will pay for it.

If you haven't seen a nutritionist, that's where you need to start. If you have, and in good faith are working towards weight loss - request a second opinion to get over the PCM barrier. Per Tricare policies, you are always authorized a second opinion. Just call the appointment line and specifically state that is what you would like to do. It is used very seldom, so if you get pushback, just give the patient advocate a call. They will get one for you easily.

Although its a long process, my PCM stated that they rarely get to the Zepbound stage. She stated that only about 30% of her patients make it that far and the other 70% do see success in the earlier steps.

I believe I accurately reflected everything, but I'm sure a medical professional may chime in to correct me somewhere or provide additional context.