displayName: DESCRIPTION SECTION
FDA Article Code: 34089-3
Metformin hydrochloride tablets and metformin hydrochloride extended-release tablets 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, USP is a white crystalline powder with a molecular formula of C4H11N5 • HCl and a molecular weight of 165.63. Metformin hydrochloride is freely soluble in water, slightly soluble in alcohol and is practically insoluble in acetone and methylene chloride. The pKa of metformin is 12.4. The pH of a 1% aqueous solution of metformin hydrochloride is 6.68.
Metformin hydrochloride tablets contain 500 mg or 850 mg or 1000 mg of metformin hydrochloride. Each tablet contains the inactive ingredients colloidal silicon dioxide, hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, povidone and sodium starch glycolate.
Metformin hydrochloride extended-release tablets contain 500 mg or 750 mg of metformin hydrochloride as the active ingredient.
Metformin hydrochloride extended-release tablets 500 mg and 750 mg contain the inactive ingredients glyceryl behenate, hypromellose, microcrystalline cellulose and povidone.
INDICATIONS AND USAGE
displayName: INDICATIONS & USAGE SECTION
FDA Article Code: 34067-9
Metformin hydrochloride tablet is indicated as an adjunct to diet and exercise to improve glycemic control in adults and children with type 2 diabetes mellitus.
Metformin hydrochloride extended-release tablet is indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus.
displayName: CONTRAINDICATIONS SECTION
FDA Article Code: 34070-3
Metformin hydrochloride tablets and metformin hydrochloride extended-release tablets are contraindicated in patients with:
1. Severe renal impairment (eGFR below 30 mL/min/1.73m2 (see
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.
displayName: ADVERSE REACTIONS SECTION
FDA Article Code: 34084-4
In a U.S. double-blind clinical study of metformin hydrochloride tablets in patients with type 2 diabetes, a total of 141 patients received metformin hydrochloride tablets therapy (up to 2550 mg per day) and 145 patients received placebo. Adverse reactions reported in greater than 5% of the metformin hydrochloride tablets patients, and that were more common in metformin hydrochloride tablets- than placebo-treated patients, are listed in Table 11.
Table 11: Most Common Adverse Reactions (>5.0 Percent) in a Placebo-Controlled Clinical Study of Metformin Hydrochloride Tablets Monotherapy
Diarrhea led to discontinuation of study medication in 6% of patients treated with metformin hydrochloride tablets. Additionally, the following adverse reactions were reported in ≥1.0 – ≤5.0% of metformin hydrochloride tablets patients and were more commonly reported with metformin hydrochloride tablets than placebo: abnormal stools, hypoglycemia, myalgia, lightheaded, dyspnea, nail disorder, rash, sweating increased, taste disorder, chest discomfort, chills, flu syndrome, flushing, palpitation.
In worldwide clinical trials over 900 patients with type 2 diabetes have been treated with metformin hydrochloride extended-release tablets in placebo- and active-controlled studies. In placebo-controlled trials, 781 patients were administered metformin hydrochloride extended-release tablets and 195 patients received placebo. 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 tablets- than placebo-treated patients, are listed in Table 12.
| Header$Adverse Reaction
| Placebo (
| Abdominal Discomfort
Table 12: Most Common Adverse Reactions (>5.0 Percent) in Placebo-Controlled Studies of Metformin Hydrochloride Extended-release Tablets
Diarrhea led to discontinuation of study medication in 0.6% of patients treated with metformin hydrochloride extended-release tablets. Additionally, the following adverse reactions were reported in 1.0% – £5.0% of metformin hydrochloride extended-release tablets patients and were more commonly reported with metformin hydrochloride extended-release tablets than placebo: abdominal pain, constipation, distention abdomen, dyspepsia/heartburn, flatulence, dizziness, headache, upper respiratory infection, taste disturbance.
Cholestatic, hepatocellular, and mixed hepatocellular liver injury have been reported with postmarketing use of metformin.
| Placebo (
displayName: OVERDOSAGE SECTION
FDA Article Code: 34088-5
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
). 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.
DOSAGE AND ADMINISTRATION
displayName: DOSAGE & ADMINISTRATION SECTION
FDA Article Code: 34068-7
There is no fixed dosage regimen for the management of hyperglycemia in patients with type 2 diabetes with metformin hydrochloride tablets or metformin hydrochloride extended-release tablets or any other pharmacologic agent. Dosage of metformin hydrochloride tablets or metformin hydrochloride extended-release tablets 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 tablets is 2550 mg in adults and 2000 mg in pediatric patients (10 years to 16 years of age); the maximum recommended daily dose of metformin hydrochloride extended-release tablets in adults is 2000 mg.
Metformin hydrochloride tablets should be given in divided doses with meals while metformin hydrochloride extended-release tablets should generally be given once daily with the evening meal. Metformin hydrochloride tablets or metformin hydrochloride extended-release tablets 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 tablets or metformin hydrochloride extended-release tablets and identify the minimum effective dose for the patient. Thereafter, glycosylated hemoglobin should be measured at intervals of approximately 3 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 tablets or metformin hydrochloride extended-release tablets, 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 tablets or metformin hydrochloride extended-release tablets may be sufficient during periods of transient loss of control in patients usually well-controlled on diet alone.
Metformin hydrochloride extended-release tablets must be swallowed whole and never crushed or chewed. Occasionally, the inactive ingredients of metformin hydrochloride extended-release tablets will be eliminated in the feces as a soft, hydrated mass (see Patient Information printed below).
displayName: HOW SUPPLIED SECTION
FDA Article Code: 34069-5
Metformin Hydrochloride Tablets, USP
Metformin Hydrochloride Tablets USP, 500 mg are white to off-white, round shaped, film-coated tablets debossed with the logo of “70” on one side and “Z” on the other side and are supplied as follows.
Unit of use Bottles of 60: 500 mg (NDC 68645-539-59)
Metformin Hydrochloride Tablets USP, 850 mg are white to off-white, oval shaped, film-coated tablets debossed with the logo of “69” on one side and “Z” on the other side and are supplied as follows.
Unit of use Bottles of 60: 850 mg (NDC 68645-549-59)
displayName: SPL MEDGUIDE SECTION
FDA Article Code: 42231-1
Metformin Hydrochloride Tablets, USP
Metformin Hydrochloride Extended-release Tablets, USP
Read this information carefully before you start taking this medicine and each time you refill your prescription. There may be new information. This information does not take the place of your doctor’s advice. Ask your doctor or pharmacist if you do not understand some of this information or if you want to know more about this medicine.
PACKAGE LABEL.PRINCIPAL DISPLAY PANEL
displayName: PACKAGE LABEL.PRINCIPAL DISPLAY PANEL
FDA Article Code: 51945-4
NDC 68645-539-59 in bottle of 60 tablets
Metformin Hydrochloride Tablets USP, 500 mg
NDC 68645-549-59 in bottle of 60 tablets
Metformin Hydrochloride Tablets USP, 850 mg