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★ "What Worked For Me" Outcome Report @ShenandoahTrail_VA • 45-59F • Tirzepatide 10 mg / Metformi • Week 30
▲ 49 Helpful • 2 Peer Replies

Semaglutide to tirzepatide switch + B12 and ferritin checks (30 wks update): Female, 45-59, type 2 diabetes on metformin 1000 mg twice daily (ER later) — what worked for others here?

Female, 45-59, type 2 diabetes on metformin 1000 mg twice daily (ER later). I plateaued on semaglutide 1 mg for 6 months, losing 6 kg. My prescriber moved me to tirzepatide 5 mg and titrated every 4-8 weeks to 10 mg. Total loss was 15 kg and A1c fell from 7.4% to 6.1%. What helped: switching metformin IR to ER with the evening meal, which cut diarrhea. I also checked B12 (it was 240 pg/mL, borderline) and ferritin (22 ng/mL), and started B12 and iron bisglycinate 25 mg. Magnesium glycinate went at bedtime, separate from iron by 2 hours. I lifted twice a week and kept protein near 100 g/day. Fatigue improved by week 12.

⚕ Pinned FDA / NIH / PubMed Clinical Context • Nourhan Mansour — Literature & Label Auditor

SURPASS-2 (NEJM 2021) showed tirzepatide 5-15 mg lowered A1c by 2.01-2.30 percentage points versus 1.86 for semaglutide 1 mg. FDA DailyMed metformin labeling recommends periodic B12 monitoring, and ferritin below 30 ng/mL indicates iron deficiency in most guidelines.

Connected Clinical Guides: Condition: Obesity Condition: Type 2 Diabetes Rx: Tirzepatide Rx: Semaglutide Supplement: Whey Protein Isolate Supplement: Creatine Monohydrate
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Verified Peer Replies (2)

@TrailKnees_UT • Verified Cohort Member • Week 20

Good detail. Label dosing for switching between GLP-1 receptor agonists isn't standardized, so the starting dose and timing should come from your prescriber. Metformin ER is typically taken with the evening meal, and it is separate from magnesium or iron only by tolerance, not by a label requirement.

@HarborSwimmer_ME • Age 60+ • Week 18

B12 was my missing piece too. After ten years on metformin mine was 195 pg/mL. Supplementing and rechecking at 12 weeks brought it into range, and the tingling in my feet improved.

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