Open Community Question @MorningFocus_IL • 45-59M • 1500mg ER + 1000mcg B12 Subl • Week 16

▲ 37 Helpful • 2 Peer Replies

1500mg Metformin ER + 1000mcg B12 Sublingual (16 wks update): Started on Metformin IR 500mg twice daily in January for type 2 diabetes — what worked for others here?

Started on Metformin IR 500mg twice daily in January for type 2 diabetes. Within 3 weeks, explosive diarrhea and severe gas ruined my compliance, and fasting glucose remained stubbornly high at 138-144 mg/dL due to morning dawn phenomenon. My practitioner transitioned me to generic Metformin ER at 500mg with my 7:00 PM dinner for week 1, 1000mg for weeks 2 and 3, and capped at 1500mg ER at week 4. Stool consistency normalized completely within 8 days. Because my baseline serum B12 was 310 pg/mL, I simultaneously added 1000 mcg sublingual methylcobalamin daily. At my week 16 lab draw: A1C down from 7.2% to 6.3%, fasting morning glucose averages 102 mg/dL, and serum B12 climbed to 640 pg/mL with zero bilateral foot paresthesia.

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

Clinical evidence confirms that Metformin ER significantly reduces gastric irritation compared to IR due to its slower dissolution rate, while concurrent B12 supplementation counteracts the drug's known 20–30% inhibition of ileal cobalamin uptake.

Connected Clinical Guides: Condition: Type 2 Diabetes Condition: Diabetes Type 2 Condition: Prediabetes Rx: Metformin Rx: Metformin Hcl Rx: Tirzepatide Supplement: Vitamin B12 Supplement: Magnesium Glycinate Supplement: Berberine

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Verified Peer Replies (2)

@DriftlessAngler_WI • Verified Cohort Member • Week 8

This protocol addresses both pharmacological challenges: the ER matrix provides a smooth Cmax that suppresses nocturnal gluconeogenesis, while proactive high-dose sublingual B12 bypasses the compromised intrinsic-factor ileal receptor pathway via passive oral mucosal diffusion.

@SteadyGlucose52 • Age 45-59 • Week 12

Confirming the same benefit here. Switching to 1500mg ER taken precisely with dinner brought my A1C from 6.9% down to 6.1% and stopped the constant stomach cramps. The B12 addition is crucial.