There's a lot of documentation online about Medicare only covering STI screening once per year. But many of those resources don't appear to have been updated since the Affordable Care Act updates in 2021. There's an FAQ document from the HHS and DOL at:
https://www.dol.gov/sites/dolgov/fi...tivities/resource-center/faqs/aca-part-47.pdf
According to the FAQ, PrEP must be covered for free by all insurance programs and since PrEP requires quarterly lab work, that must be covered for free as well. The FAQ implies that Medicare or Medicaid should cover it, but it doesn't explicitly state it. All the other guidance documentation on the CMS.gov site comes from circa 2010 and obviously won't reflect recent changes.
You may need to look into testing from your local public health authority or community clinic that can access Medicaid funds to cover it. An article notes that a lot of places still haven't gotten the message that PrEP and its associated tests should be covered.
PrEP, the HIV prevention pill, must now be totally free under almost all insurance plans
Also ran across this:
Medicare Coverage for Truvada
Good luck!