Metformin Hcl Prescribing Information
WARNING: LACTIC ACIDOSIS Postmarketing cases of metformin-associated lactic acidosis have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias. The onset of metformin-associated lactic acidosis is often subtle, accompanied only by nonspecific symptoms such as malaise, myalgias, respiratory distress, somnolence, and abdominal pain. Metformin-associated lactic acidosis was characterized by elevated blood lactate levels (>5 mmol/Liter), anion gap acidosis (without evidence of ketonuria or ketonemia), an increased lactate/pyruvate ratio; and metformin plasma levels generally >5 mcg/mL [see Warnings and Precautions (5.1) ]. Risk factors for metformin-associated lactic acidosis include renal impairment, concomitant use of certain drugs (e.g. carbonic anhydrase inhibitors such as topiramate), age 65 years old or greater, having a radiological study with contrast, surgery and other procedures, hypoxic states (e.g., acute congestive heart failure), excessive alcohol intake, and hepatic impairment. Steps to reduce the risk of and manage metformin-associated lactic acidosis in these high risk groups are provided [see Dosage and Administration (2.3) , Contraindications (4) , Warnings and Precautions (5.1) ]. If metformin-associated lactic acidosis is suspected, immediately discontinue Metformin Hydrochloride Tablets and institute general supportive measures in a hospital setting. Prompt haemodialysis is recommended [see Warnings and Precautions (5.1) ]. |
Metformin Hydrochloride Tablets, USP is indicated as an adjunct to diet and exercise to improve glycemic control in adults and pediatric patients 10 years of age and older with type 2 diabetes mellitus.
- The recommended starting dose of Metformin Hydrochloride Tablet is 500 mg orally twice a day or 850 mg once a day, given with meals.
- Increase the dose in increments of 500 mg weekly or 850 mg every 2 weeks on the basis of glycemic control and tolerability, up to a maximum dose of 2550 mg per day, given in divided doses.
- Doses above 2000 mg may be better tolerated given 3 times a day with meals.
- The recommended starting dose of Metformin Hydrochloride Tablet for pediatric patients 10 years of age and older is 500 mg orally twice a day, given with meals.
- Increase dosage in increments of 500 mg weekly on the basis of glycemic control and tolerability, up to a maximum of 2000 mg per day, given in divided doses twice daily.
- Assess renal function prior to initiation of Metformin Hydrochloride Tablet and periodically thereafter.
- Metformin Hydrochloride Tablet is contraindicated in patients with an estimated glomerular filtration rate (eGFR) below 30 mL/minute/1.73 m
2. - Initiation of Metformin Hydrochloride Tablet in patients with an eGFR between 30 – 45 mL/minute/1.73 m
2is not recommended. - In patients taking Metformin Hydrochloride Tablet whose eGFR later falls below 45 mL/min/1.73 m
2, assess the benefit risk of continuing therapy. - Discontinue Metformin Hydrochloride Tablet if the patient’s eGFR later falls below 30 mL/minute/1.73 m
2[see Warnings and Precautions (5.1) ].
Discontinue Metformin Hydrochloride Tablet at the time of, or prior to, an iodinated contrast imaging procedure in patients with an eGFR between 30 and 60 mL/min/1.73 m
2; in patients with a history of liver disease, alcoholism, or heart failure; or in patients who will be administered intraarterial iodinated contrast. Re-evaluate eGFR 48 hours after the imaging procedure; restart Metformin Hydrochloride Tablet if renal function is stable.
Metformin Hydrochloride Tablet is available as:
- 500 mg:white to off-white colored, film coated, round shaped tablet with beveled edges on both side and debossed with ‘134’ on one side and plain on other side.
- 850 mg:white to off-white colored, film coated, round shaped tablet with beveled edges on both side and debossed with ‘131’ on one side and plain on other side.
- 1000 mg:white to off-white colored, film coated, oval shaped tablet with ‘132’ debossed on one side and breakline on both sides.
Metformin Hydrochloride 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.