This was true in 2019 (when that comment was posted), but changed in 2021. I looked up the details because of @baeddel's post since it seemed a thing that would be easy to fix by petition for rulemaking. Here's the updated info, cross posted from Reddit:
Four years ago, u/Rarvyn noted that Medicare required 4 home blood glucose monitor (BGM) tests per day to qualify for a continuous glucose monitor (CGM), but only provided 3 per day.
I happened across that post via a recent Tumblr post about it. I was curious about the details and whether a quick petition for rulemaking could solve it.
Medicare.gov has only vague blather, so I looked up cms.gov's serious version of the Medicare guidance & requirements on diabetes supplies and on CGMs.
This rule did exist in 2019, but was changed 2021-07-18, in revision 8:
Removed: Four times or more per day testing with blood glucose monitor as prerequisite for CGM coverage
That was done in response to many comments filed 2020-12 through 2021-01 asking for the "4/day" rule to be reconsidered (among other changes).
ETA: here's an even more detailed update from u/Rarvyn, the endocrinologist MD who posted the original.
The current (2023-05-13) Medicare requirements for diabetes equipment coverage are, summarizing the links above:
home glucose monitor (HGM)
adapted versions of HGM if needed for disability (eg blindness, motor control)
≤100/3mo if no insulin treatment
≤300/3mo if yes insulin treatment
more allowed if extra Rx for "high utilization" need w/ regular monitoring of usage
continuous glucose monitor (CGM)
diagnosed with diabetes mellitus
≥2 level 2 hypoglycemic events (glucose <54mg/dL / 3.0mmol/L) despite ≥2 attempts to adjust treatment
≥1 level 3 hypoglycemic event (same glucose threshold) w/ altered mental/physical state needing third-party assistance for treatment of hypoglycemia
