Metformin HCl 500 mg Tablet, 180-count
🆔 Identity & classification
Where does this data come from?
🏷️ RxNorm drug class
This medicine belongs to the Biguanide class.
Where does this data come from?
🏭 Manufacturer & labeler
Where does this data come from?
🩺 Clinical
Metformin is used alone or with other medications, including insulin, to treat type 2 diabetes (condition in which the body does not use insulin normally and, therefore, cannot control the amount of sugar in the blood). Metformin is in a class of drugs called biguanides. Metformin helps to control the amount of glucose (sugar) in your blood. It decreases the amount of glucose you absorb from your food and the amount of glucose made by your liver. Metformin also increases your body's response to insulin, a natural substance that controls the amount of glucose in the blood. Metformin is not used...
Read the full MedlinePlus article ↗- No, and that's actually one of the things that makes metformin different. It doesn't force your pancreas to produce more insulin. Instead, it works in three ways: it tells your liv...
- What exactly does metformin do — does it just push my pancreas to make more insulin?
- Stomach upset, nausea, and diarrhea are really common at the start, and they can be significant for some people. The good news is they usually improve as your body adjusts. Always...
- The stomach side effects sound rough — is there anything I can do about them?
Patient education
Supplement & herbal interactions
Metformin may be associated with lower levels of 4 nutrients — worth a chat with your pharmacist, not a cause for alarm.
Where does this data come from?
Ask a licensed pharmacist directly — free, answered by our team.
💊 What it looks like
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🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.
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UNII 0WZ8WG20P6
Hypromellose 2910 is a plant-based cellulose derivative that acts as a thickener, binder, and film-coating agent. It helps control how quickly the medicine dissolves and protects the tablet or capsule from moisture and light.
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UNII 70097M6I30
Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
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UNII 7CVR7L4A2D
A starch-derived carbohydrate produced by breaking down corn, potato, or tapioca starch. It functions as a filler and binder to give the medicine bulk and texture, and sometimes as a mild sweetener or texture enhancer in powders and tablets.
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UNII B697894SGQ
Polyethylene glycol 400 is a clear, thick liquid made from petroleum-derived polymers. It acts as a solvent and humectant in medicines, helping dissolve active ingredients and retain moisture in the formulation.
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UNII U725QWY32X
Povidone K30 is a synthetic polymer made from petroleum. It acts as a binder to hold tablet ingredients together and as a disintegrant to help the tablet break apart in the stomach so the medicine can be absorbed.
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UNII RDH86HJV5Z
Povidone K90 is a synthetic polymer made from a chemical called vinyl pyrrolidone. It acts as a binder to hold pill ingredients together and as a dispersant to help the medicine break down and dissolve properly in your body.
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UNII O8232NY3SJ
A plant-based carbohydrate derived from corn kernels. It acts as a filler to add bulk, a binder to hold ingredients together, and a disintegrant to help the tablet break apart in your stomach for absorption.
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UNII XHX3C3X673
Triacetin is a clear, oily liquid made from glycerin and acetic acid. It works as a plasticizer and solvent in medicines, helping soften coatings and improve how liquids mix together in formulations.
8 inactive ingredients listed in the exact product block matched to this NDC.
Where does this data come from?
ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.Inactive ingredient FAQ
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Can inactive ingredients matter?
💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per each | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data. | |
| Medicare drug plans payPart D · Q2 2026 | $0.0671 | $12.08 / 180 tablets |
Where does this data come from?
🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Metformin Hydrochloride 500 mg 71093-0132-04 | ACI | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 00378-7185-05 | Mylan | 500 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 00904-7162-61 | Major | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 23155-0841-01 | Heritage | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 42385-0947-01 | Laurus | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin HCl 500 mg 49483-0622-01 | TIME | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 59651-0854-01 | Aurobindo | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 60687-0155-01 | American | 1 tablet | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 62135-0680-05 | Chartwell | 500 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 65862-0008-01 | Aurobindo | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin HCl 500 mg 67877-0561-01 | Ascend | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 67877-0930-01 | Ascend | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 68094-0688-60 | Precision | 500 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 68382-0758-01 | Zydus | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin hydrochloride 500 mg 68645-0582-59 | Legacy | 60 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 69367-0180-01 | Westminster | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 69367-0381-01 | Westminster | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 70010-0063-01 | Granules | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 82009-0046-10 | Quallent | 1000 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 82009-0174-10 | Quallent | 1000 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 83301-0008-01 | Mullan | 100 tablets | $0.014 | AB | Availability likely | — |
| Metformin Hydrochloride 500 mg 24658-0790-01 | PuraCap | 100 tablets | $0.017 | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 00615-8015-05 | NCS | 15 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 00615-8629-05 | NCS | 15 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 25000-0134-03 | MARKSANS | 30 tablets | — | AB | FDA listed | — |
| Metformin hydrochloride 500 mg 33342-0141-10 | Macleods | 90 tablets | — | — | FDA listed | — |
| Metformin HCl 500 mg 42708-0009-60 | QPharma, | 60 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 42806-0313-01 | Epic | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 43063-0527-14 | PD-Rx | 14 tablets | — | — | FDA listed | — |
| Metformin Hydrochloride 500 mg 43353-0982-30 | Aphena | 30 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-2081-00 | A-S | 60 tablets | — | AB | FDA listed | — |
| Metformin HCl 500 mgthis 50090-3064-05 | A-S | 180 tablets | — | AB | FDA listed | — |
| Metformin HCl 500 mg 50090-4891-00 | A-S | 90 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-6485-00 | A-S | 90 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-6858-00 | A-S | 60 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-6859-00 | A-S | 90 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-7010-00 | A-S | 60 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-7011-00 | A-S | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-7013-00 | A-S | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-7278-00 | A-S | 60 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-7280-00 | A-S | 90 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-7595-00 | A-S | 60 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50090-7597-00 | A-S | 90 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 50228-0105-00 | ScieGen | 9000 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 51655-0556-25 | Northwind | 60 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 53746-0218-01 | Amneal | 100 tablets | — | — | FDA listed | — |
| Metformin Hydrochloride 500 mg 55154-4172-00 | Cardinal | 10 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 60429-0111-01 | Golden | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 62207-0440-43 | Granules | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 63187-0238-90 | Proficient | 90 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 63629-8501-01 | Bryant | 500 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 63629-8502-01 | Bryant | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 67046-0298-03 | Coupler | 30 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 67046-1594-03 | Coupler | 30 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 67877-0217-01 | Ascend | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 68071-3518-08 | NuCare | 180 tablets | — | AB | FDA listed | — |
| Metformin HCl 500 mg 68071-3541-06 | NuCare | 60 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 68071-3739-01 | NuCare | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 68071-3900-06 | NuCare | 60 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 68788-4076-01 | Preferred | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 68788-8498-01 | Preferred | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 68788-8564-01 | Preferred | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 68788-8652-01 | Preferred | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 70518-1149-01 | REMEDYREPACK | 1 tablet | — | AB | Discontinued | — |
| Metformin Hydrochloride 500 mg 70518-1951-01 | REMEDYREPACK | 30 tablets | — | AB | Discontinued | — |
| Metformin Hydrochloride 500 mg 70518-2833-00 | REMEDYREPACK | 30 tablets | — | AB | FDA listed | — |
| Metformin HCl 500 mg 70882-0124-56 | Cambridge | 56 tablets | — | AB | Discontinued | — |
| Metformin HCl 500 mg 71205-0562-00 | Proficient | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71205-0622-30 | Proficient | 30 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71205-0784-30 | Proficient | 30 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71205-0882-00 | Proficient | 100 tablets | — | AB | FDA listed | — |
| Metformin HCl 500 mg 71335-1072-00 | Bryant | 25 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71335-1834-00 | Bryant | 25 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71335-2224-00 | Bryant | 25 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71335-2466-00 | Bryant | 25 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71335-3132-00 | Bryant | 25 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71610-0917-30 | Aphena | 30 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71610-0920-53 | Aphena | 60 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71610-0929-30 | Aphena | 30 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 71709-0110-06 | Metcure | 500 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 72162-1522-01 | Bryant | 100 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 72189-0219-30 | direct | 30 tablets | — | AB | FDA listed | — |
| Metformin HCL 500 mg 72189-0617-30 | Direct_Rx | 30 tablets | — | AB | FDA listed | — |
| Metformin HCL 500 mg 72189-0658-30 | Direct_Rx | 30 tablets | — | AB | FDA listed | — |
| Metformin HCl 500 mg 72789-0192-20 | PD-Rx | 20 tablets | — | AB | FDA listed | — |
| Metformin HCl 500 mg 72789-0531-42 | PD-Rx | 42 tablets | — | AB | FDA listed | — |
| Metformin Hydrochloride 500 mg 72789-0561-20 | PD-Rx | 20 tablets | — | AB | FDA listed | — |
| Metformin HCl 500 mg 82868-0049-90 | Northwind | 90 tablets | — | AB | FDA listed | — |
| Metformin HCl 500 mg 87441-0056-01 | Unit | 30 tablets | — | AB | FDA listed | — |
Where does this data come from?
⏳ Availability & generic status
This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.
Where does this data come from?
📊 Medicare Part D spend CMS · PART D · 2026 (Q1)
🔬 Reported adverse events (FAERS)
Top reported reactions
Age at onset
Reporter sex
Serious outcomes
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📦 Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Status |
|---|---|---|---|
| 50090-3064-00 | 60 TABLET in 1 BOTTLE, PLASTIC (50090-3064-0) | 2017-02-06 | Active |
| 50090-3064-03 | 100 TABLET in 1 BOTTLE (50090-3064-3) | 2017-07-13 | Active |
| 50090-3064-04 | 30 TABLET in 1 BOTTLE (50090-3064-4) | 2017-06-16 | Active |
| 50090-3064-05 You're viewing this | 180 TABLET in 1 BOTTLE, PLASTIC (50090-3064-5) | 2017-02-06 | Active |
| 50090-3064-06 | 90 TABLET in 1 BOTTLE, PLASTIC (50090-3064-6) | 2017-02-06 | Active |
You're viewing the largest of 5 pack sizes for this product.
Pack size FAQ
What quantity is in NDC 50090-3064-05?
What is the difference between NDC 50090-3064-05 and NDC 50090-3064-04?
What NDC number is used to bill for this package of Metformin HCl 500 mg Tablet?
🧭 About this NDC listing & data coverage
What data is (and isn’t) available for this NDC — tap to expand
| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | ✓ Available |
| Inactive ingredients (structured) | ✓ Available |
| NADAC pharmacy acquisition price (CMS) | — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey. |
| Orange Book / therapeutic-equivalence data | ✓ Available |
| HCPCS J-code billing crosswalk | — Not published for this NDC Most self-administered / retail products have no J-code — that is normal. |
| Medicaid utilization (CMS SDUD) | — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold. |
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📄 Full prescribing information FDA SPL
🎯 Indications and Usage ▾
INDICATIONS & USAGE Metformin Hydrochloride Tablets USP are indicated as an adjunct to diet and exercise to improve glycemic control in adults and children with type 2 diabetes mellitus.
⏱️ Dosage and Administration ▾
DOSAGE & ADMINISTRATION There is no fixed dosage regimen for the management of hyperglycemia in patients with type 2 diabetes with metformin hydrochloride or any other pharmacologic agent. Dosage of metformin hydrochloride must be individualized on the basis of both effectiveness and tolerance, while not exceeding the maximum recommended daily doses. The maximum recommended daily dose of metformin hydrochloride is 2550 mg in adults and 2000 mg in pediatric patients (10 to 16 years of age).
Metformin hydrochloride should be given in divided doses with meals. Metformin hydrochloride should be started at a low dose, with gradual dose escalation, both to reduce gastrointestinal side effects and to permit identification of the minimum dose required for adequate glycemic control of the patient. During treatment initiation and dose titration (see Recommended Dosing Schedule ), fasting plasma glucose should be used to determine the therapeutic response to metformin hydrochloride and identify the minimum effective dose for the patient.
Thereafter, glycosylated hemoglobin should be measured at intervals of approximately three months. The therapeutic goal should be to decrease both fasting plasma glucose and glycosylated hemoglobin levels to normal or near normal by using the lowest effective dose of metformin hydrochloride, either when used as monotherapy or in combination with sulfonylurea or insulin. Monitoring of blood glucose and glycosylated hemoglobin will also permit detection of primary failure, i.e., inadequate lowering of blood glucose at the maximum recommended dose of medication, and secondary failure, i.e., loss of an adequate blood glucose lowering response after an initial period of effectiveness.
Short-term administration of metformin hydrochloride may be sufficient during periods of transient loss of control in patients usually well-controlled on diet alone. Recommended Dosing Schedule Adults – In general, clinically significant responses are not seen at doses below 1500 mg per day. However, a lower recommended starting dose and gradually increased dosage is advised to minimize gastrointestinal symptoms.
The usual starting dose of metformin hydrochloride is 500 mg twice a day or 850 mg once a day, given with meals. Dosage increases should be made in increments of 500 mg weekly or 850 mg every 2 weeks, up to a total of 2000 mg per day, given in divided doses. Patients can also be titrated from 500 mg twice a day to 850 mg twice a day after 2 weeks.
For those patients requiring additional glycemic control, metformin hydrochloride may be given to a maximum daily dose of 2550 mg per day. Doses above 2000 mg may be better tolerated given three times a day with meals. If higher doses of metformin are required, metformin hydrochloride should be used at total daily doses up to 2550 mg administered in divided daily doses, as described above.
(See CLINICAL PHARMACOLOGY: Clinical Studies .) Pediatrics – The usual starting dose of metformin hydrochloride is 500 mg twice a day, given with meals. Dosage increases should be made in increments of 500 mg weekly up to a maximum of 2000 mg per day, given in divided doses. Transfer From Other Antidiabetic Therapy When transferring patients from standard oral hypoglycemic agents other than chlorpropamide to metformin hydrochloride, no transition period generally is necessary.
When transferring patients from chlorpropamide, care should be exercised during the first two weeks because of the prolonged retention of chlorpropamide in the body, leading to overlapping drug effects and possible hypoglycemia. Concomitant Metformin Hydrochloride and Oral Sulfonylurea Therapy in Adult Patients If patients have not responded to four weeks of the maximum dose of metformin hydrochloride monotherapy, consideration should be given to gradual addition of an oral sulfonylurea while continuing metformin hydrochloride at the maximum dose, even if prior primary or secondary failure to a sulfonylurea has occurre…
⛔ Contraindications ▾
CONTRAINDICATIONS Metformin Hydrochloride Tablets USP are contraindicated in patients with: 1. Renal disease or renal dysfunction (e.g., as suggested by serum creatinine levels ≥1.5 mg/dL [males], ≥1.4 mg/dL [females] or abnormal creatinine clearance) which may also result from conditions such as cardiovascular collapse (shock), acute myocardial infarction, and septicemia (see WARNINGS and PRECAUTIONS ). 2.
Known hypersensitivity to metformin hydrochloride 3. Acute or chronic metabolic acidosis, including diabetic ketoacidosis, with or without coma. Diabetic ketoacidosis should be treated with insulin.
Metformin Hydrochloride Tablets USP should be temporarily discontinued in patients undergoing radiologic studies involving intravascular administration of iodinated contrast materials, because use of such products may result in acute alteration of renal function. (See also PRECAUTIONS .)
⚠️ Warnings ▾
WARNINGS Lactic Acidosis: Lactic acidosis is a rare, but serious, metabolic complication that can occur due to metformin accumulation during treatment with Metformin Hydrochloride Tablets USP; when it occurs, it is fatal in approximately 50% of cases. Lactic acidosis may also occur in association with a number of pathophysiologic conditions, including diabetes mellitus, and whenever there is significant tissue hypoperfusion and hypoxemia. Lactic acidosis is characterized by elevated blood lactate levels (>5 mmol/L), decreased blood pH, electrolyte disturbances with an increased anion gap, and an increased lactate/pyruvate ratio.
When metformin is implicated as the cause of lactic acidosis, metformin plasma levels >5 mcg/mL are generally found. The reported incidence of lactic acidosis in patients receiving metformin hydrochloride is very low (approximately 0.03 cases/1000 patient-years, with approximately 0.015 fatal cases/1000 patient-years). In more than 20,000 patient-years exposure to metformin in clinical trials, there were no reports of lactic acidosis.
Reported cases have occurred primarily in diabetic patients with significant renal insufficiency, including both intrinsic renal disease and renal hypoperfusion, often in the setting of multiple concomitant medical/surgical problems and multiple concomitant medications. Patients with congestive heart failure requiring pharmacologic management, in particular those with unstable or acute congestive heart failure who are at risk of hypoperfusion and hypoxemia, are at increased risk of lactic acidosis. The risk of lactic acidosis increases with the degree of renal dysfunction and the patient’s age.
The risk of lactic acidosis may, therefore, be significantly decreased by regular monitoring of renal function in patients taking Metformin Hydrochloride Tablets USP and by use of the minimum effective dose of Metformin Hydrochloride Tablets USP. In particular, treatment of the elderly should be accompanied by careful monitoring of renal function. Metformin Hydrochloride Tablets USP treatment should not be initiated in patients ≥80 years of age unless measurement of creatinine clearance demonstrates that renal function is not reduced, as these patients are more susceptible to developing lactic acidosis.
In addition, Metformin Hydrochloride Tablets USP should be promptly withheld in the presence of any condition associated with hypoxemia, dehydration, or sepsis. Because impaired hepatic function may significantly limit the ability to clear lactate, Metformin Hydrochloride Tablets USP should generally be avoided in patients with clinical or laboratory evidence of hepatic disease. Patients should be cautioned against excessive alcohol intake, either acute or chronic, when taking Metformin Hydrochloride Tablets USP, since alcohol potentiates the effects of metformin hydrochloride on lactate metabolism.
In addition, Metformin Hydrochloride Tablets USP should be temporarily discontinued prior to any intravascular radiocontrast study and for any surgical procedure (see also PRECAUTIONS). The onset of lactic acidosis often is subtle, and accompanied only by nonspecific symptoms such as malaise, myalgias, respiratory distress, increasing somnolence, and nonspecific abdominal distress. There may be associated hypothermia, hypotension, and resistant bradyarrhythmias with more marked acidosis.
The patient and the patient’s physician must be aware of the possible importance of such symptoms and the patient should be instructed to notify the physician immediately if they occur (see also PRECAUTIONS). Metformin Hydrochloride Tablets USP should be withdrawn until the situation is clarified. Serum electrolytes, ketones, blood glucose, and if indicated, blood pH, lactate levels, and even blood metformin levels may be useful.
Once a patient is stabilized on any dose level of Metformin Hydrochloride Tablets USP, gastrointestinal symptoms, which are common during initiation of therapy, are unlikely to…
🤒 Adverse Reactions ▾
ADVERSE REACTIONS In a US double-blind clinical study of Metformin Hydrochloride Tablets USP in patients with type 2 diabetes, a total of 141 patients received Metformin Hydrochloride Tablets USP therapy (up to 2550 mg per day) and 145 patients received placebo. Adverse reactions reported in greater than 5% of the Metformin Hydrochloride Tablets USP patients, and that were more common in Metformin Hydrochloride Tablets USP- than placebo-treated patients, are listed in Table 9 . Table 9: Most Common Adverse Reactions (>5.0 Percent) in a Placebo-Controlled Clinical Study of Metformin Hydrochloride Tablets Monotherapy * Adverse Reaction Metformin Hydrochloride Tablets Monotherapy (n=141) Placebo (n=145) % of Patients Diarrhea 53.2
11.7Nausea/Vomiting 25.5
8.3Flatulence 12.1
5.5Asthenia 9.2
5.5Indigestion 7.1
4.1Abdominal Discomfort 6.4
4.8Headache 5.7 4.8 * Reactions that were more common in metformin hydrochloride tablets than placebo-treated patients. Diarrhea led to discontinuation of study medication in 6% of patients treated with Metformin Hydrochloride Tablets USP. Additionally, the following adverse reactions were reported in ≥1.0 to ≤5.0% of Metformin Hydrochloride Tablets USP patients and were more commonly reported with Metformin Hydrochloride Tablets USP than placebo: abnormal stools, hypoglycemia, myalgia, lightheaded, dyspnea, nail disorder, rash, sweating increased, taste disorder, chest discomfort, chills, flu syndrome, flushing, palpitation.
Pediatric Patients In clinical trials with Metformin Hydrochloride Tablets USP in pediatric patients with type 2 diabetes, the profile of adverse reactions was similar to that observed in adults.
🔄 Drug Interactions ▾
DRUG INTERACTIONS (Clinical Evaluation of Drug Interactions Conducted with Metformin Hydrochloride Tablets USP) Glyburide —In a single-dose interaction study in type 2 diabetes patients, coadministration of metformin and glyburide did not result in any changes in either metformin pharmacokinetics or pharmacodynamics. Decreases in glyburide AUC and C max were observed, but were highly variable. The single-dose nature of this study and the lack of correlation between glyburide blood levels and pharmacodynamic effects, makes the clinical significance of this interaction uncertain (see DOSAGE AND ADMINISTRATION: Concomitant Metformin Hydrochloride Tablets USP and Oral Sulfonylurea Therapy in Adult Patients ).
Furosemide —A single-dose, metformin-furosemide drug interaction study in healthy subjects demonstrated that pharmacokinetic parameters of both compounds were affected by coadministration. Furosemide increased the metformin plasma and blood C max by 22% and blood AUC by 15%, without any significant change in metformin renal clearance. When administered with metformin, the C max and AUC of furosemide were 31% and 12% smaller, respectively, than when administered alone, and the terminal half-life was decreased by 32%, without any significant change in furosemide renal clearance.
No information is available about the interaction of metformin and furosemide when coadministered chronically. Nifedipine —A single-dose, metformin-nifedipine drug interaction study in normal healthy volunteers demonstrated that coadministration of nifedipine increased plasma metformin C max and AUC by 20% and 9%, respectively, and increased the amount excreted in the urine. T max and half-life were unaffected.
Nifedipine appears to enhance the absorption of metformin. Metformin had minimal effects on nifedipine. Cationic drugs —Cationic drugs (e.g., amiloride, digoxin, morphine, procainamide, quinidine, quinine, ranitidine, triamterene, trimethoprim, or vancomycin) that are eliminated by renal tubular secretion theoretically have the potential for interaction with metformin by competing for common renal tubular transport systems.
Such interaction between metformin and oral cimetidine has been observed in normal healthy volunteers in both single- and multiple-dose, metformin-cimetidine drug interaction studies, with a 60% increase in peak metformin plasma and whole blood concentrations and a 40% increase in plasma and whole blood metformin AUC. There was no change in elimination half-life in the single-dose study. Metformin had no effect on cimetidine pharmacokinetics.
Although such interactions remain theoretical (except for cimetidine), careful patient monitoring and dose adjustment of Metformin Hydrochloride Tablets USP and/or the interfering drug is recommended in patients who are taking cationic medications that are excreted via the proximal renal tubular secretory system. Other —Certain drugs tend to produce hyperglycemia and may lead to loss of glycemic control. These drugs include the thiazides and other diuretics, corticosteroids, phenothiazines, thyroid products, estrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics, calcium channel blocking drugs, and isoniazid.
When such drugs are administered to a patient receiving Metformin Hydrochloride Tablets USP, the patient should be closely observed for loss of blood glucose control. When such drugs are withdrawn from a patient receiving Metformin Hydrochloride Tablets USP, the patient should be observed closely for hypoglycemia. In healthy volunteers, the pharmacokinetics of metformin and propranolol, and metformin and ibuprofen were not affected when coadministered in single-dose interaction studies.
Metformin is negligibly bound to plasma proteins and is, therefore, less likely to interact with highly protein-bound drugs such as salicylates, sulfonamides, chloramphenicol, and probenecid, as compared to the sulfonylureas, which are extensively bound to serum proteins.
🔄 Drug / Laboratory Test Interactions ▾
DRUG & OR LABORATORY TEST INTERACTIONS
🤰 Pregnancy ▾
PREGNANCY Teratogenic Effects: Pregnancy Category B Recent information strongly suggests that abnormal blood glucose levels during pregnancy are associated with a higher incidence of congenital abnormalities. Most experts recommend that insulin be used during pregnancy to maintain blood glucose levels as close to normal as possible. Because animal reproduction studies are not always predictive of human response, Metformin Hydrochloride Tablets USP should not be used during pregnancy unless clearly needed.
There are no adequate and well-controlled studies in pregnant women with Metformin Hydrochloride Tablets USP. Metformin was not teratogenic in rats and rabbits at doses up to 600 mg/kg/day. This represents an exposure of about two and six times the maximum recommended human daily dose of 2000 mg based on body surface area comparisons for rats and rabbits, respectively.
Determination of fetal concentrations demonstrated a partial placental barrier to metformin.
🧒 Pediatric Use ▾
PEDIATRIC USE The safety and effectiveness of Metformin Hydrochloride Tablets USP for the treatment of type 2 diabetes have been established in pediatric patients ages 10 to 16 years (studies have not been conducted in pediatric patients below the age of 10 years). Use of Metformin Hydrochloride Tablets USP in this age group is supported by evidence from adequate and well-controlled studies of Metformin Hydrochloride Tablets USP in adults with additional data from a controlled clinical study in pediatric patients ages 10 to 16 years with type 2 diabetes, which demonstrated a similar response in glycemic control to that seen in adults.
(See CLINICAL PHARMACOLOGY: Pediatric Clinical Studies .) In this study, adverse effects were similar to those described in adults. (See ADVERSE REACTIONS: Pediatric Patients. ) A maximum daily dose of 2000 mg is recommended. (See DOSAGE AND ADMINISTRATION: Recommended Dosing Schedule: Pediatrics. )
🧓 Geriatric Use ▾
GERIATRIC USE Controlled clinical studies of Metformin Hydrochloride Tablets USP did not include sufficient numbers of elderly patients to determine whether they respond differently from younger patients, although other reported clinical experience has not identified differences in responses between the elderly and younger patients. Metformin is known to be substantially excreted by the kidney and because the risk of serious adverse reactions to the drug is greater in patients with impaired renal function, Metformin Hydrochloride Tablets USP should only be used in patients with normal renal function (see CONTRAINDICATIONS, WARNINGS , and CLINICAL PHARMACOLOGY: Pharmacokinetics ).
Because aging is associated with reduced renal function, Metformin Hydrochloride Tablets USP should be used with caution as age increases. Care should be taken in dose selection and should be based on careful and regular monitoring of renal function. Generally, elderly patients should not be titrated to the maximum dose of Metformin Hydrochloride Tablets USP (see also WARNINGS and DOSAGE AND ADMINISTRATION ).
🆘 Overdosage ▾
OVERDOSAGE Overdose of metformin hydrochloride has occurred, including ingestion of amounts greater than 50 grams. Hypoglycemia was reported in approximately 10% of cases, but no causal association with metformin hydrochloride has been established. Lactic acidosis has been reported in approximately 32% of metformin overdose cases (see WARNINGS ).
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.
🧬 Clinical Pharmacology ▾
CLINICAL PHARMACOLOGY Mechanism of Action Metformin is an antihyperglycemic agent which improves glucose tolerance in patients with type 2 diabetes, lowering both basal and postprandial plasma glucose. Its pharmacologic mechanisms of action are different from other classes of oral antihyperglycemic agents. Metformin decreases hepatic glucose production, decreases intestinal absorption of glucose, and improves insulin sensitivity by increasing peripheral glucose uptake and utilization.
Unlike sulfonylureas, metformin does not produce hypoglycemia in either patients with type 2 diabetes or normal subjects (except in special circumstances, see PRECAUTIONS) and does not cause hyperinsulinemia. With metformin therapy, insulin secretion remains unchanged while fasting insulin levels and day-long plasma insulin response may actually decrease. Pharmacokinetics Absorption and Bioavailability The absolute bioavailability of a Metformin Hydrochloride 500 mg tablet given under fasting conditions is approximately 50% to 60%.
Studies using single oral doses of Metformin Hydrochloride 500 mg to 1500 mg, and 850 mg to 2550 mg, indicate that there is a lack of dose proportionality with increasing doses, which is due to decreased absorption rather than an alteration in elimination. Food decreases the extent of and slightly delays the absorption of metformin, as shown by approximately a 40% lower mean peak plasma concentration (C max ), a 25% lower area under the plasma concentration versus time curve (AUC), and a 35-minute prolongation of time to peak plasma concentration (T max ) following administration of a single 850 mg tablet of metformin with food, compared to the same tablet strength administered fasting.
The clinical relevance of these decreases is unknown. Distribution The apparent volume of distribution (V/F) of metformin following single oral doses of Metformin Hydrochloride Tablets USP 850 mg averaged 654 ± 358 L. Metformin is negligibly bound to plasma proteins, in contrast to sulfonylureas, which are more than 90% protein bound.
Metformin partitions into erythrocytes, most likely as a function of time. At usual clinical doses and dosing schedules of Metformin Hydrochloride Tablets USP, steady state plasma concentrations of metformin are reached within 24 to 48 hours and are generally <1mcg/mL. During controlled clinical trials of Metformin Hydrochloride Tablets USP, maximum metformin plasma levels did not exceed 5 mcg/mL, even at maximum doses.
Metabolism and Elimination Intravenous single-dose studies in normal subjects demonstrate that metformin is excreted unchanged in the urine and does not undergo hepatic metabolism (no metabolites have been identified in humans) nor biliary excretion. Renal clearance (see Table 1) is approximately 3.5 times greater than creatinine clearance, which indicates that tubular secretion is the major route of metformin elimination. Following oral administration, approximately 90% of the absorbed drug is eliminated via the renal route within the first 24 hours, with a plasma elimination half-life of approximately 6.2 hours.
In blood, the elimination half-life is approximately 17.6 hours, suggesting that the erythrocyte mass may be a compartment of distribution. Special Populations Patients with Type 2 Diabetes In the presence of normal renal function, there are no differences between single- or multiple-dose pharmacokinetics of metformin between patients with type 2 diabetes and normal subjects (see Table 1 ), nor is there any accumulation of metformin in either group at usual clinical doses Renal Insufficiency In patients with decreased renal function (based on measured creatinine clearance), the plasma and blood half-life of metformin is prolonged and the renal clearance is decreased in proportion to the decrease in creatinine clearance (see Table 1 ; also see WARNINGS ).
Hepatic Insufficiency No pharmacokinetic studies of metformin have been conducted in patients with hepatic insufficiency. Geriat…
📦 How Supplied / Storage and Handling ▾
HOW SUPPLIED Product: 50090-3064 NDC: 50090-3064-3 100 TABLET in a BOTTLE NDC: 50090-3064-4 30 TABLET in a BOTTLE NDC: 50090-3064-0 60 TABLET in a BOTTLE, PLASTIC NDC: 50090-3064-5 180 TABLET in a BOTTLE, PLASTIC NDC: 50090-3064-6 90 TABLET in a BOTTLE, PLASTIC
📦 Storage and Handling ▾
Storage Store at 20°–25° C (68°–77° F); excursions permitted to 15°–30° C (59°–86° F). [See USP Controlled Room Temperature.] Dispense in tight, light-resistant containers with child-resistant closure.
📋 Description ▾
DESCRIPTION Metformin Hydrochloride Tablets USP are oral antihyperglycemic drugs used in the management of type 2 diabetes. Metformin hydrochloride (N,N-dimethylimidodicarbonimidic diamide hydrochloride) is not chemically or pharmacologically related to any other classes of oral antihyperglycemic agents. The structural formula is as shown: Metformin hydrochloride is a white to off-white crystalline compound with a molecular formula of C 4 H 11 N 5 • HCl and a molecular weight of 165.63.
Metformin hydrochloride is freely soluble in water and is practically insoluble in acetone, ether, and chloroform. The pKa of metformin is 12.4. The pH of a 1% aqueous solution of metformin hydrochloride is 6.68.
Metformin Hydrochloride Tablets USP contain 500 mg, 850 mg, or 1000 mg of metformin hydrochloride. Each tablet contains the inactive ingredients povidone (K-30), povidone (K-90), pregelatinized starch,and magnesium stearate. In addition, the coating for the tablets contains artificial blackberry flavor, hypromellose and polyethylene glycol.
Metformin Hydrochloride Structure
💬 Information for Patients ▾
INFORMATION FOR PATIENTS Patients should be informed of the potential risks and benefits of Metformin Hydrochloride Tablets USP and of alternative modes of therapy. They should also be informed about the importance of adherence to dietary instructions, of a regular exercise program, and of regular testing of blood glucose, glycosylated hemoglobin, renal function, and hematologic parameters. The risks of lactic acidosis, its symptoms, and conditions that predispose to its development, as noted in the WARNINGS and PRECAUTIONS sections, should be explained to patients.
Patients should be advised to discontinue Metformin Hydrochloride Tablets USP immediately and to promptly notify their health practitioner if unexplained hyperventilation, myalgia, malaise, unusual somnolence, or other nonspecific symptoms occur. Once a patient is stabilized on any dose level of Metformin Hydrochloride Tablets USP, gastrointestinal symptoms, which are common during initiation of metformin therapy, are unlikely to be drug related. Later occurrence of gastrointestinal symptoms could be due to lactic acidosis or other serious disease.
Patients should be counselled against excessive alcohol intake, either acute or chronic, while receiving Metformin Hydrochloride Tablets USP. Metformin Hydrochloride Tablets USP alone do not usually cause hypoglycemia, although it may occur when Metformin Hydrochloride Tablets USP are used in conjunction with oral sulfonylureas and insulin. When initiating combination therapy, the risks of hypoglycemia, its symptoms and treatment, and conditions that predispose to its development should be explained to patients and responsible family members.
(See Patient Information printed below.)