A year on Mounjaro for T2D: what the A1C charts do not show

I was diagnosed with type 2 diabetes in early 2025 at 34. A1C 8.2, fasting glucose 165. My endocrinologist suggested Mounjaro as first-line monotherapy after metformin gave me significant GI side effects I could not tolerate.

The glucose change came faster than the weight change. Within four weeks of starting (still on 2.5 mg, the starter dose) my fasting glucose was in the 110s. By month three at 7.5 mg it was in the 90s. My A1C dropped from 8.2 to 6.8 by month six and now sits at 6.6.

The weight angle: I have lost 38 lbs over the year, which is more than I expected given that I am not on the maximum dose (I am at 10 mg, which works well for my glucose). Mounjaro's dual GIP/GLP-1 mechanism really does suppress appetite differently than a single-mechanism drug — I have read enough about tirzepatide vs semaglutide to know that anecdotally most patients describe it the same way.

What the A1C charts do not show: the first 6 weeks were genuinely difficult. Not from the medication directly — from rebuilding my entire eating identity. I had eaten three large meals a day plus snacks for 34 years. Mounjaro broke that pattern within a week. Smaller meals, less frequent, often skipping breakfast. Restaurants became uncomfortable because I could only finish half a normal portion.

The injection ritual itself is unremarkable. The pen is single-use, the dose is pre-dialed, the needle is so thin you barely feel it. I inject Thursday evenings so I sleep through any peak nausea. I have learned to plan low-fat meals on Friday.

A year in: A1C 6.6, BMI down from 32 to 28, sleep apnea risk gone, blood pressure normalized. My endocrinologist is talking about possibly stepping me down to a lower dose for maintenance. Mounjaro got me here; the lifestyle changes around it are what will keep me here.