Metformin is a biguanide sold in the U.S. under 7 brand and generic names, for type 2 diabetes mellitus. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
From the FDA label for Glucophage (application NDA020357). Other metformin products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
Adult Dosage Swallow Metformin Hydrochloride Extended-Release Tablets whole and never crush, cut or chew. The recommended starting dose of Metformin Hydrochloride Extended-Release Tablet is 500 mg orally once daily with the evening meal. Increase the dose in increments of 500 mg weekly on the basis of glycemic control and tolerability, up to a maximum of 2000 mg once daily with the evening meal. If glycemic control is not achieved with Metformin Hydrochloride Extended-Release Tablet 2000 mg once daily, consider a trial of Metformin Hydrochloride Extended-Release Tablet 1000 mg twice daily. If higher doses are required, switch to Metformin Hydrochloride at total daily doses up to 2550 mg administered in divided daily doses, as described above. Patients receiving Metformin Hydrochloride Tablets may be switched to Metformin Hydrochloride Extended-Release Tablet once daily at the same total daily dose, up to 2000 mg once daily. 2.3 Recommendations for Use in Renal Impairment Assess renal function prior to initiation of Metformin Hydrochloride Extended-Release Tablet and periodically thereafter. Metformin Hydrochloride Extended-Release Tablet is contraindicated in patients with an estimated glomerular filtration rate (eGFR) below 30 mL/minute/1.73 m 2 . Initiation of Metformin Hydrochloride Extended-Release Tablet in patients with an eGFR between 30 – 45 mL/minute/1.73 m 2 is not…
The following adverse reactions are also discussed elsewhere in the labeling: Lactic Acidosis [ see Boxed Warning and Warnings and Precautions (5.1)] Vitamin B 12 Deficiency [see Warnings and Precautions (5.2)] Hypoglycemia [see Warnings and Precautions (5.3)] 6.1 Clinical Studies Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Metformin Hydrochloride Extended-Release Tablets In placebo-controlled trials, 781 patients were administered metformin hydrochloride extended-release tablets. Adverse reactions reported in greater than 5% of the metformin hydrochloride extended-release tablets patients, and that were more common in metformin hydrochloride extended-release tablet -than placebo-treated patients, are listed in Table 2. Table 2: Adverse Reactions from Clinical Trials of Metformin Hydrochloride Extended-Release Tablets Occurring >5% and More Common than Placebo in Patients with Type 2 Diabetes Mellitus Metformin Hydrochloride Extended-Release Tablets (n=781) Placebo (n=195) Diarrhea 10% 3% Nausea/Vomiting 7% 2% Diarrhea led to discontinuation of metformin hydrochloride extended-release tablets in 0.6% of patients. Additionally, the following adverse…
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
| # | Drug | Rating | Type | Form | Generic? | Typical price | |
|---|---|---|---|---|---|---|---|
| 1 | 72/100 | Prescription | Solution | Generic | $1 | View → | |
| 2 |
Imprint codes, colour and shape from the FDA’s labelling data. Match the imprint on your pill — or search any imprint.
| Imprint | Strength | Colour | Shape | Maker |
|---|---|---|---|---|
| G;12 | 1000 mg | white | oval | — |
| 0018;1000 | 1000 mg | white | round | — |
| SM2 | 5 mg / 1000 mg | pink | oval | — |
| SM1 | 2.5 mg / 1000 mg | yellow | oval | — |
| 385;12;5;2;5 | 12.5 mg / 2.5 mg / 1000 mg | red | oval | — |
| SM6;M | 5 mg / 1000 mg |
A combination is a different drug — different dosing, different warnings. It is listed here so you can find it, not so you can substitute it.
From the FDA Enforcement database. A recall covers specific lots — not the drug as a whole.
Metformin Hydrochloride Extended-Release Tablets 1000mg
CGMP Deviations
Glenmark Pharmaceuticals Inc., USA · Mar 13, 2025
METFORMIN HYDROCHLORIDE EXTENDED- RELEASE 500MG
Presence of Foreign Tablets/Capsules.
A-S Medication Solutions LLC · Feb 25, 2025
Metformin Hydrochloride Extended-Release Tablets
Presence of Foreign Tablets/Capsules: A Paracetamol 500 mg tablet was found in a 1000-count bottle of Metformin HCL ER Tablets USP, 500 mg.
Granules Pharmaceuticals Inc. · Dec 30, 2024
The elimination half-life of metformin is about 6.2 hours (plasma elimination half-life in adults with normal kidney function). Metformin is not metabolized and has no active metabolites, so 6.2 hours reflects the parent drug. The often-cited ~17.6-hour "blood" half-life reflects the drug lingering in red blood cells (distribution), not parent-drug elimination. The half-life is prolonged when kidney function is reduced.
Metformin Hydrochloride Tablets, USP — DailyMed (Clinical Pharmacology / Pharmacokinetics) ↗Half-life is how long the body takes to clear half a dose. It is not the same as how long a drug test can detect it, and it varies with age, kidney and liver function.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Metformin hydrochloride extended-release tablets are contraindicated in patients with: Severe renal impairment (eGFR below 30 mL/min/1.73 m 2 ) [see Warnings and Precautions (5.1)] . Hypersensitivity to metformin Acute or chronic metabolic acidosis, including diabetic ketoacidosis, with or without coma. Severe renal impairment (eGFR below 30 mL/min/1.73 m 2 ) (4, 5.1) Hypersensitivity to metformin (4) Acute or chronic metabolic acidosis, including diabetic ketoacidosis, with or without coma. (4)
Table 3 presents clinically significant drug interactions with metformin hydrochloride extended-release tablets. Table 3: Clinically Significant Drug Interactions with metformin hydrochloride extended-release tablets Carbonic Anhydrase Inhibitors Clinical Impact: Carbonic anhydrase inhibitors frequently cause a decrease in serum bicarbonate and induce non-anion gap, hyperchloremic metabolic acidosis. Concomitant use of these drugs with metformin hydrochloride extended-release tablets may increase the risk for lactic acidosis. Intervention: Consider more frequent monitoring of these patients. Examples: Topiramate, zonisamide, acetazolamide or dichlorphenamide. Drugs that Reduce Metformin Hydrochloride Extended-Release Tablets Clearance Clinical Impact: Concomitant use of drugs that interfere with common renal tubular transport systems involved in the renal elimination of metformin (e.g., organic cationic transporter-2 [OCT2] / multidrug and toxin extrusion [MATE] inhibitors) could increase systemic exposure to metformin and may increase the risk for lactic acidosis [see Clinical Pharmacology (12.3)]. Intervention: Consider the benefits and risks of concomitant use with metformin hydrochloride extended-release tablets. Examples: Ranolazine, vandetanib, dolutegravir, and cimetidine. Alcohol Clinical Impact: Alcohol is known to potentiate the effect of metformin on lactate…
| 70/100 |
| Prescription |
| Tablet |
| Generic |
| $1 |
| View → |
| 3 | 70/100 | Prescription | Tablet | Generic | $1 | View → |
| 4 | 68/100 | Prescription | Solution | Generic | $1 | View → |
| 5 | Not yet rated | Prescription | Tablet | Generic | $1 | View → |
| 6 | Not yet rated | Prescription | Tablet | Generic | $1 | View → |
| 7 | Not yet rated | Prescription | Suspension | Generic | $1 | View → |
| pink |
| oval |
| — |
| SM4;M | 2.5 mg / 1000 mg | orange | oval | — |
|---|
| S5;1000 | 5 mg / 1000 mg | brown | oval | — |
|---|
| S12;500 | 12.5 mg / 500 mg | purple | oval | — |
|---|
| 2;5;1000 | 2.5 mg / 1000 mg | pink | oval | — |
|---|
| 7;5;500 | 7.5 mg / 500 mg | red | oval | — |
|---|
| 7;5;1000 | 7.5 mg / 1000 mg | red | oval | — |
|---|