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Metformin

Metformin hydrochloride extended-release tablets are a biguanide indicated as an adjunct to diet and exercise to improve glycemic control in adults wi.

Prescription medicine Oral Safety alerts on record

How to use Metformin

What the official label says. If a doctor prescribed it, follow the prescription. Your pack's leaflet comes first if it is different.

Serious warning: LACTIC ACIDOSIS WARNING: LACTIC ACIDOSIS See full prescribing information for complete boxed warning. Postmarketing cases of metformin-associated lactic acidosis have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias. Symptoms included malaise, myalgias, respiratory distress, somnolence, and abdominal pain. …
Who it is for

Metformin hydrochloride extended-release tablets are a biguanide indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. ( 1 ) Metformin hydrochloride extended-release tablets are indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus.

How to take it and how often
  • Swallow metformin hydrochloride extended-release tablets whole and never crush, cut or chew Starting dose: 500 mg orally once daily with the evening meal Increase the dose in increments of 500 mg weekly, up to a maximum of 2,000 mg once daily with the evening meal Patients receiving metformin hydrochloride (HCl) tablets may be switched to metformin hydrochloride extended-release tablets once daily at the same total daily dose, up to 2,000 mg once daily Renal Impairment: Prior to initiation, assess renal function with estimated glomerular filtration rate (eGFR) Do not use in patients with eGFR below 30 mL/minute/1.73 m 2 Initiation is not recommended in patients with eGFR between 30 to 45 mL/minute/1.73 m 2 Assess risk/benefit of continuing if eGFR falls below 45 mL/minute/1.73 m 2 Discontinue if eGFR falls below 30 mL/minute/1.73 m 2 Discontinuation for Iodinated Contrast Imaging Procedures: Metformin hydrochloride extended-release tablets may need to be discontinued at time of, or prior to, iodinated contrast imaging procedures Adult Dosage and Administration
  • Swallow metformin hydrochloride extended-release tablets whole and never crush, cut or chew
  • The recommended starting dose of metformin hydrochloride extended-release tablets 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 2,000 mg once daily with the evening meal. …
Strengths it comes in

Extended-Release Tablets: 500 mg and 1,000 mg ( 3 ) Metformin hydrochloride extended-release tablets are available as: Extended-release tablets : 1,000 mg white-colored tablets imprinted with "NL1" on one side.

Children
  • Safety and effectiveness of metformin hydrochloride extended-release tablets
  • In pediatric patients have not been established
Older adults

Controlled clinical studies of metformin hydrochloride extended-release tablets did not include sufficient numbers of elderly patients to determine whether they respond differently from younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug …

While you are taking it
  • Advise the patient to read the FDA-approved patient labeling (Patient Information)
  • Lactic Acidosis: Explain the risks of lactic acidosis, its symptoms, and conditions that predispose to its development
  • Advise patients to discontinue metformin hydrochloride extended-release tablets immediately and to promptly notify their healthcare provider if unexplained hyperventilation, myalgias, malaise, unusual somnolence or other nonspecific symptoms occur
  • Counsel patients against excessive alcohol intake and inform patients about importance of regular testing of renal function while receiving metformin hydrochloride extended-release tablets. …
Talk to a doctor first if
  • Severe renal impairment (eGFR below 30 mL/min/1.73 m 2 ) Hypersensitivity to metformin Acute or chronic metabolic acidosis, including diabetic ketoacidosis, with or without coma
  • 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 ]
  • Hypersensitivity to metformin. …
Medicines it may not mix with

Carbonic anhydrase inhibitors may increase risk of lactic acidosis. Consider more frequent monitoring ( 7 ) Drugs that reduce metformin clearance (such as ranolazine, vandetanib, dolutegravir, and cimetidine) may increase the accumulation of metformin. Consider the benefits and risks of concomitant use ( 7 ) Alcohol can potentiate the effect of metformin on lactate metabolism. Warn patients against excessive alcohol intake ( 7 ) Table 2 presents clinically significant drug interactions with metformin hydrochloride extended-release tablets. table2-1 table2-2

Warnings

Lactic Acidosis: See boxed warning . ( 5.1 ) Vitamin B 12 Deficiency: Metformin may lower vitamin B 12 levels. Measure hematological parameters annually and vitamin B 12 at 2 to 3 year intervals and manage any abnormalities. ( 5.2 ) Hypoglycemia with Concomitant Use with Insulin and Insulin Secretagogues: Increased risk of hypoglycemia when used in combination with insulin and/or an insulin secretagogue. Lower dose of insulin or insulin secretagogue may be required. ( 5.3 ) 5.1 Lactic Acidosis There have been postmarketing cases of metformin-associated lactic acidosis, including fatal cases. …

Possible side effects

Common adverse reactions are diarrhea, nausea/vomiting, abdominal pain, constipation, abdomen distention, dyspepsia/heartburn, flatulence, dizziness, headache, upper respiratory infection, taste disturbance. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Ingenus Pharmaceuticals, LLC Toll-Free at 1-877-748-1970 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. …

Pregnancy and breastfeeding

8.1 Pregnancy Risk Summary Limited data with metformin hydrochloride extended-release tablets in pregnant women are not sufficient to determine a drug-associated risk for major birth defects or miscarriage. Published studies with metformin use during pregnancy have not reported a clear association with metformin and major birth defect or miscarriage risk [see Data ] . …

If you take too much

Overdose of metformin HCl has occurred, including ingestion of amounts greater than 50 grams. Hypoglycemia was reported in approximately 10% of cases, but no causal association with metformin has been established. Lactic acidosis has been reported in approximately 32% of metformin overdose cases [see Warnings and Precautions (5.1) ] . Metformin is dialyzable with a clearance of up to 170 mL/min under good hemodynamic conditions. Therefore, hemodialysis may be useful for removal of accumulated drug from patients in whom metformin overdosage is suspected.

If you miss a dose

Take it when you remember, unless it is nearly time for the next dose. Then skip the missed one. Never take two doses at once to make up for it. Check your leaflet, as some medicines are different.

From the official U.S. FDA label for this active ingredient. Your pack may have a different strength, so always read its leaflet. If a doctor prescribed it, follow the prescription. Ask a pharmacist if you are unsure. Label dated 2026-05-01.

Brands around the world

Products with Metformin as the active ingredient. Names differ between countries.

Registered products

United States (FDA)

Metformin HydrochlorideMETFORMIN HYDROCHLORIDE 500 mg/1 · Tablet, Film Coated · A-S Medication Solutions
NDC 50090-8043Label
Metformin HydrochlorideMETFORMIN HYDROCHLORIDE 1000 mg/1 · Tablet · Coupler LLC
NDC 67046-1516Label
Saxagliptin And Metformin HydrochlorideSAXAGLIPTIN 2.5 mg/1, METFORMIN HYDROCHLORIDE 1000 mg/1 · Tablet, Film Coated, Extended Release · Dr.Reddys Laboratories Inc
NDC 43598-618Label
MetforminMETFORMIN HYDROCHLORIDE 500 mg/1 · Tablet, Extended Release · Coupler LLC
NDC 67046-0437Label
Metformin HydrochlorideMETFORMIN HYDROCHLORIDE 500 mg/1 · Tablet · Preferred Pharmaceuticals Inc.
NDC 68788-8564Label

Nigeria (NAFDAC)

NAFDACMetformin Tablets C4-1668NAFDACMetformin 500 mg Tablet A4-2278NAFDACMetformin 1000 mg Tablet B4-7689NAFDACMetformin 1000 mg Tablets C4-1431NAFDACMetformin Sandoz 850 mg Tablets B4-2915NAFDACMetformin 500 mg Tablet## (check pack size) A4-8314NAFDACMetformin Hydrochloride 500 mg & Glimepiride 2 mg Tablet C4-1280NAFDACGlyformin 04-7968NAFDACMelanov - M B4-3166NAFDACDiamet Tablet 04-7945NAFDACRyphage 500 mg A11-100150NAFDACSuphage Tablet B4-3759

Other countries: check your pack's registration number and we point you to your regulator.

Safety alerts and recalls

Synjardy XR Tablets (empagliflozin and metformin hydrochloride extended-release tablets), 12.5/1000 mg, 60 Tablets per Bottle, Rx only, Distributed by: Boehringer Ingelheim PharmacU.S. FDA Class II
12 Jun 2026 · Boehringer Ingelheim Pharmaceuticals, Inc. · OngoingCGMP Deviations: An incorrect detergent was used and the required swab sampling was not performed on a production hopper that had previously been used for a different product.
Metformin Hydrochloride Extended-Release Tablets 1000mg, 90-count bottle. Manufactured by: Glenmark Pharmaceuticals Limited, Pithampur, Madhya Pradesh 454775, India, Manufactured fU.S. FDA Class II
13 Mar 2025 · Glenmark Pharmaceuticals Inc., USA · OngoingCGMP Deviations
METFORMIN HYDROCHLORIDE EXTENDED- RELEASE 500MG, 180 TABLETS, Packaged BY: A-S Medication Solutions, Libertyville, IL 60048 NDC 50090-1494-3.U.S. FDA Class II
25 Feb 2025 · A-S Medication Solutions LLC · OngoingPresence of Foreign Tablets/Capsules.
Metformin Hydrochloride Extended-Release Tablets, USP, 500 mg, 1000-count bottles, Rx Only, Manufactured by: Granules India Limited, Hyderabad- 500 081, India, Manufactured for: QuU.S. FDA Class II
30 Dec 2024 · Granules Pharmaceuticals Inc. · TerminatedPresence of Foreign Tablets/Capsules: A Paracetamol 500 mg tablet was found in a 1000-count bottle of Metformin HCL ER Tablets USP, 500 mg.

A recall usually affects certain batches only. Compare the lot number on your pack.

Check your pack of Metformin

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3 free checks left today Official sources: U.S. FDA · EMA (EU) · NAFDAC · WHO alerts

Questions about Metformin

What is Metformin used for?

Metformin hydrochloride extended-release tablets are a biguanide indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. ( 1 ) Metformin hydrochloride extended-release tablets are indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. (From the official U.S. FDA label.)

How do I take Metformin?

Follow your prescription or the leaflet in your pack. The official label says: Swallow metformin hydrochloride extended-release tablets whole and never crush, cut or chew ( 2.1 ) Starting dose: 500 mg orally once daily with the evening meal ( 2.1 ) Increase the dose in increments of 500 mg weekly, up to a maximum of 2,000 mg once daily with the evening meal ( 2.1 ) Patients receiving metformin hydrochloride (HCl) tablets may be switched to metformin hydro…

Do I need a prescription for Metformin?

Usually yes. Metformin is a prescription medicine in most countries. Rules differ by country.

What brands contain Metformin?

Metformin is sold under names such as Kazano, Jentadueto, Kombiglyze, Janumet, Glucophage, Invokamet, Xigduo, Synjardy. Brand names differ between countries.

How can I check that my Metformin is genuine?

Scan the registration number on your pack with PillVera (NAFDAC number in Nigeria, NDC in the United States, DIN in Canada), check the expiry date and buy only from licensed pharmacies.