Metformin
Type 2 diabetes mellitus (first-line), Prediabetes (off-label), PCOS (off-label)
Indications
- Type 2 diabetes mellitus (first-line)
- Prediabetes (off-label)
- PCOS (off-label)
Adult dosing
- standard: dose: 500; unit: mg; route: PO BID; interval: Titrate to 1000mg BID over 2-4 weeks; fixed: true; extended release: dose: 500; unit: mg; route: PO daily with dinner; interval: Titrate to 2000mg daily; fixed: true
Contraindications
- eGFR <30
- Acute or chronic metabolic acidosis
- Hold 48h after iodinated contrast
Clinical pearls
- Start low, go slow — GI side effects (nausea, diarrhea) are dose-limiting; ER formulation is better tolerated
- No hypoglycemia risk as monotherapy
- Hold before surgery and resume when eating normally and renal function confirmed stable
- Lactic acidosis is rare but hold in acute illness with risk of hypoperfusion
Source and review
- ADA Standards of Care 2024. Last reviewed: 2024-11-01