Select a medication above to begin.
metformin
generic
Black Box Warnings .
Lactic Acidosis
post-marketing cases of hypothermia, hypotension, resistant bradyarrhythmias, and death; onset may be subtle w/ nonspecific sx incl. malaise, myalgias, resp. distress, somnolence, abdominal pain; lab findings incl. lactate >5 mmol/L, anion gap acidosis (w/o evidence of ketonuria or ketonemia), incr. lactate/pyruvate ratio, metformin level >5 mcg/mL; risk factors may incl. renal impairment, concomitant meds, pts 65 yo and older, radiocontrast study, any surgery, hypoxemia, excessive acute or chronic alcohol intake, or hepatic insufficiency; D/C metformin immed. if lactic acidosis suspected, hospitalize pt and institute general supportive care, prompt HD recommended
Adult Dosing .
Dosage forms: TAB: 500 mg, 850 mg, 1000 mg; ER TAB: 500 mg, 750 mg, 1000 mg; SOL: 500 mg per 5 mL
diabetes mellitus, type 2
- [immediate-release form]
- Dose: 850-1000 mg PO bid; Start: 850 mg PO qd or 500 mg PO bid, incr. by 500 mg/day qwk or 850 mg/day q2wk as tolerated; Max: 2550 mg/day; Info: give w/ meals; hold tx for surgery if restricting food/fluid; D/C for iodinated contrast study if eGFR 30-60, hepatic dz hx, alcoholism hx, heart failure hx, or receiving contrast intra-arterially; restart after 48h if stable renal fxn
- [extended-release form]
- Dose: 1000-2000 mg ER PO qpm; Start: 500 mg ER PO qpm, incr. by 500 mg/day qwk as tolerated; Max: 2000 mg/day ER; Alt: 1000 mg ER PO bid; Info: may add 500 mg regular form if inadequate response; give w/ meals; do not cut/crush/chew ER tab; hold tx for surgery if restricting food/fluid; D/C for iodinated contrast study if eGFR 30-60, hepatic dz hx, alcoholism hx, heart failure hx, or receiving contrast intra-arterially; restart after 48h if stable renal fxn
diabetes mellitus prevention, type 2 (off-label)
- [850 mg PO bid]
- Start: 850 mg PO qd x1mo; Info: for pts w/ prediabetes; give w/ meals; hold tx for surgery if restricting food/fluid; D/C for iodinated contrast study if eGFR 30-60, hepatic dz hx, alcoholism hx, heart failure hx, or receiving contrast intra-arterially; restart after 48h if stable renal fxn
polycystic ovary syndrome (off-label)
- [immediate-release form]
- Dose: 500 mg PO tid; Max: 2550 mg/day; Alt: 850-1000 mg PO bid; Info: may incr. dose if inadequate response; give w/ meals; hold tx for surgery if restricting food/fluid; D/C for iodinated contrast study if eGFR 30-60, hepatic dz hx, alcoholism hx, heart failure hx, or receiving contrast intra-arterially; restart after 48h if stable renal fxn
- [extended-release form]
- Dose: 1500-2000 mg ER PO qpm; Info: give w/ meals; do not cut/crush/chew ER tab; hold tx for surgery if restricting food/fluid; D/C for iodinated contrast study if eGFR 30-60, hepatic dz hx, alcoholism hx, heart failure hx, or receiving contrast intra-arterially; restart after 48h if stable renal fxn
renal dosing
- [diabetes mellitus, type 2]
- eGFR 30-44: avoid tx initiation; eGFR <30: contraindicated; Alt: decr. usual dose by 50% if eGFR 30-44
- HD/PD: avoid use
- [all other indications]
- eGFR 30-44: avoid tx initiation; eGFR <30: contraindicated; Info: weigh risk/benefit if eGFR 30-44 during tx
- HD/PD: avoid use
hepatic dosing
- [see below]
- hepatic impairment: avoid use
Peds Dosing .
- Dosage forms: TAB: 500 mg, 850 mg, 1000 mg; SOL: 500 mg per 5 mL
diabetes mellitus, type 2
- [10-16 yo]
- Dose: 500-1000 mg PO bid; Start: 500 mg PO qd, incr. by 500 mg/day q1-2wk as tolerated; Max: 2000 mg/day; Info: give w/ meals; hold tx for surgery if restricting food/fluid; D/C for iodinated contrast study if eGFR 30-60, hepatic dz hx, alcoholism hx, heart failure hx, or receiving contrast intra-arterially; restart after 48h if stable renal fxn
- [17 yo and older]
- Dose: 850-1000 mg PO bid; Start: 850 mg PO qd or 500 mg PO bid, incr. by 500 mg/day qwk or 850 mg/day q2wk as tolerated; Max: 2550 mg/day; Info: give w/ meals; hold tx for surgery if restricting food/fluid; D/C for iodinated contrast study if eGFR 30-60, hepatic dz hx, alcoholism hx, heart failure hx, or receiving contrast intra-arterially; restart after 48h if stable renal fxn
renal dosing
- [see below]
- eGFR 30-44: avoid tx initiation; eGFR <30: contraindicated; Info: weigh risk/benefit if eGFR 30-44 during tx
- HD/PD: avoid use
hepatic dosing
- [see below]
- hepatic impairment: avoid use