Metformin
Sold as Glucophage, Fortamet, Glumetza
Metformin is the first-line oral medication for type 2 diabetes. It lowers the amount of glucose your liver makes and helps your body respond better to insulin.
As of August 2026, Metformin (500 mg) cash prices on BetterBuyRx start at $3.96 across 8 verified sources (lowest at Blink Health). The free BetterBuyRx discount card recently showed $3.51 in the 553xx ZIP area (checked Aug 22, 2026); card prices vary by ZIP, so enter yours on the drug page for local pharmacy prices. Prices change; confirm at the counter.
What it treats
Type 2 diabetes mellitus, alone or with other diabetes drugs.
Typical dosing
Max dose differs by formulation, do not assume one number: • Immediate-release (IR), e.g. Glucophage: max 2550 mg/day, given in divided doses (typically 2-3x/day with meals). Usual starting dose 500 mg twice daily, titrated slowly to reduce GI side effects. • Extended-release (XR/ER), e.g. Glucophage XR, Fortamet, Glumetza: max is generally 2000 mg/day (Glucophage XR label); check the specific product's FDA label, as some ER formulations (e.g. Fortamet) are approved up to 2500 mg/day. Taken once daily, usually with the evening meal.
Monitoring
Kidney function (eGFR) before starting and at least annually (more often if at risk). Metformin is contraindicated at eGFR below 30 mL/min/1.73m² due to lactic-acidosis risk; dose should be reassessed and often reduced at eGFR 30-45. Periodic vitamin B12 levels with long-term use.
Side effects
Common: nausea, diarrhea, gas, metallic taste, usually improves in 1-2 weeks. Rare but serious: lactic acidosis, more likely with kidney impairment, dehydration, or heavy alcohol use. Long-term use can lower vitamin B12, periodic B12 monitoring is recommended, especially with anemia or neuropathy symptoms.
Interactions to know
Tell your doctor before any imaging study with IV contrast, metformin may need to be held around the procedure. Alcohol increases lactic acidosis risk.
Pregnancy & breastfeeding
Generally considered safe in pregnancy; discuss with your obstetrician.
Live price snapshot
| Source | Type | Cash price |
|---|---|---|
| Blink Health | pharmacy | $3.96 |
| Mark Cuban Cost Plus | pharmacy | $5.62 |
| Honeybee Health | pharmacy | $7.20 |
| Costco Pharmacy | pharmacy | $7.50 |
| Walmart $4/$10 generic list | program | $9.00 |
| H-E-B Pharmacy | program | $10.00 |
Save with the free BetterBuyRx card
The BetterBuyRx discount card is free, no signup, no insurance needed. It recently showed $3.51 for Metformin at a partner-network pharmacy in the 553xx ZIP area, card prices vary by ZIP, so enter yours on the drug page for local pharmacy prices. Show the card at the pharmacy counter; it can't be combined with insurance.
Frequently asked questions
- How much does Metformin cost without insurance?
- As of the latest check, the lowest verified cash price we've found for Metformin is $3.96 at Blink Health, across 8 verified sources. Cash prices are unregulated and vary by pharmacy, so compare before you fill and confirm the price at the counter.
- Is there a generic for Metformin?
- Yes. Metformin is the generic; it is also sold under brand names such as Glucophage, Fortamet, Glumetza. The generic is typically far cheaper than brand and is what our verified cash prices reflect.
- Can I use the free BetterBuyRx discount card for Metformin?
- Yes. The free BetterBuyRx discount card recently showed $3.51 for this medication at a partner-network pharmacy in the 553xx ZIP area (checked Aug 22, 2026). Card prices vary by ZIP, enter yours on the drug page to see local pharmacy prices. Show the card (BIN, PCN, Group, and Member ID where required) at the counter; it can't be combined with insurance.
- Why does the price of Metformin vary so much between pharmacies?
- U.S. cash prescription prices are unregulated, each pharmacy sets its own markup, and discount programs and mail-order sources widen the spread further (this is common across the Biguanide class). That's why comparing verified prices before you fill can save money.
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Clinical content reviewed by the BetterBuyRx clinical team, on 2026-07-07.
Educational only. Not medical advice. Always confirm with your prescriber or pharmacist.