[riceart]

Has nothing to do with it. A1c measures the percentage of hemoglobin A1 in red blood cells bound to sugars (glycated hemoglobin). Since red blood cells normally circulate for months this gives a surrogate marker for average blood glucose levels over 3-6 months.

Dehydration is not a confounder for an A1c test since the percentage is relative to the hemoglobin present. The primary confounder to A1c are blood disorders such as hemolytic anemias that lower the normal lifetime of RBCs or proportion of HbA. And this tends to falsely lower the A1c.

A person with an 11% A1c is also likely drinking quite a bit (whether they notice it or not) because at that point the chronically elevated glucose is elevating serum osmolality to increase urination.

[rblatz]

Dehydration and kidney damage is a common side effect of Semaglutide, and they regularly test for that if you are on it. Drinking plenty of water is the way to prevent that from happening.

[riceart]

Perhaps I misunderstood what the GP was asking. Nevertheless GLP-1 medications appear to be kidney protective from a long term standpoint with an increased short term risk of AKI likely primarily related to GI losses with additional risk conveyed by concomitant use of “depleting” (diuretics) and nephrotoxic meds. Once on a stable dose there’s no current recommendation to monitor kidney function beyond what would normally be indicated for diabetes (usually yearly).