RiteMED Metformin HCl

Adjunct to diet & exercise to improve glycemic control in patients w/ type 2 DM. May be used as monotherapy or in combination w/ other oral antidiabetic agents or w/ insulin.

Individualized dose. Tab/FC tab Adult ≥17 yr Initially 500 mg bid or 850 mg once daily, may be increased in increments of 500 mg wkly or 850 mg every 2 wk up to a total of 2,000 mg daily in divided doses. After 2 wk, patients can also be titrated from 500 mg bid to 850 mg bid. Max dose: 2,550 mg daily, given in divided doses. Doses >2,000 mg may be better tolerated if given in 3 divided doses. Childn 10-16 yr Initially 500 mg bid or 850 mg once daily,  may be increased in increments of 500 mg wkly up to a max of 2,000 mg daily in divided doses. Concomitant insulin therapy Initially 500 mg or 850 mg once daily, may be increased by 500 mg after approx 1 wk & by 500 mg every wk thereafter until adequate glycemic control is achieved. Max recommended dose w/ insulin: 2,550 mg daily. SR tab Adult ≥17 yr Initially 500 mg once daily, may be increased in increments of 500 mg wkly up to a max of 2,000 mg once daily. If glycemic control w/ 2,000 mg once daily remains unsatisfactory, a dose of 1,000 mg bid may be considered. Max dose: 2,000 mg daily.

Should be taken with food.

Hypersensitivity. Unstable &/or type 1 IDDM. History of lactic acidosis irrespective of precipitating factors. Acute or chronic metabolic acidosis, including diabetic ketoacidosis, w/ or w/o coma. Acute conditions w/ potential to alter renal function eg, dehydration (due to persistent or severe diarrhea, recurrent vomiting), severe infection, diagnostic exam (eg, IV urography, angiography) that involves use of iodinated contrast agents/media. Acute or chronic disease which may cause tissue hypoxia eg, cardiac or resp failure, recent MI, shock. Acute or chronic alcoholism. Severe renal impairment (eGFR <30 mL/min/1.73 m²). Severe liver disease. Pregnancy or lactation.

Discontinue use in patients w/ lactic acidosis; those undergoing surgery associated w/ restricted food or fluid intake; in periods of stress eg, fever, trauma, infection, or surgery. Do not use in patients w/ CHF receiving drugs eg, digoxin & furosemide. Macrovascular risk reduction has not been established. Hypoglycemia could occur when caloric intake is deficient when strenuous exercise is not compensated by caloric supplementation, or in concomitant use w/ other glucose-lowering agents (eg, sulfonylureas & insulin) or ethanol; especially in elderly, debilitated or malnourished patients, & those w/ adrenal or pituitary insufficiency or alcohol intoxication. Promptly discontinue use if hypoxic states occur during therapy. Assess renal function prior to initiation of therapy, & more frequently in patients at increased risk for development of renal failure. Determine eGFR at least annually in all patients. Evaluate hematologic parameters prior to initiation of therapy & at least annually. Discontinue use at the time of, or prior to, an iodinated contrast imaging procedure in patients w/ eGFR 30-60 mL/min/1.73 m², history of liver disease, alcoholism, or heart failure, or those administered w/ intraarterial iodinated contrast, & re-evaluate eGFR 48 hr after the imaging procedure & restart treatment if renal function is stable. Avoid excessive alcohol intake on an acute or chronic basis. Concomitant use w/ medications which may affect renal function or result in significant hemodynamic change or interfere w/ disposition ie, cationic drugs. Not recommended to be initiated in patients w/ eGFR 30-45 mL/min/1.73 m². Discontinue use if eGFR later falls <30 mL/min/1.73 m². Avoid in patients w/ clinical or lab evidence of hepatic disease. Elderly. Caution when driving a vehicle or operating machinery. SR tab: Safety & efficacy in childn have not been established.

Nausea, vomiting, diarrhea, abdominal pain & loss of appetite.

Peak plasma conc & whole blood conc & AUC may be increased w/ cationic drugs eliminated by renal tubular secretion eg, amiloride, digoxin, morphine, procainamide, quinidine, quinine, ranitidine, triamterene, trimethoprim, & vancomycin. Reduced urinary excretion & increased plasma conc w/ cimetidine. Hypoglycemia may occur w/ other antidiabetic agents eg, sulfonylureas, meglitinides, glitazones, or insulin. May exacerbate DM & may result in increased requirements of metformin w/ thiazide diuretics. Temporary loss of diabetic control or secondary failure to metformin may also occur w/ thiazide diuretics. Plasma conc & blood conc & AUC may be increased w/o significantly affecting renal clearance w/ furosemide. Increased absorption, C_max, AUC & urine excretion w/ nifedipine. May impair glucose tolerance & mask the true frequency or severity of hypoglycemia, block hypoglycemia-induced tachycardia (but not hypoglycemic sweating), delay rate of recovery of blood glucose conc following drug-induced hypoglycemia, & impair peripheral circulation w/ β-adrenergic blockers eg, propranolol, nadolol. May reduce fasting blood glucose conc w/ ACE inhibitors eg, captopril, enalapril. Increased risk of hypoglycemia & lactic acidosis w/ alcohol. May increase ovulatory response w/ clomifene in premenopausal patients w/ PCOS. May affect pharmacokinetic properties of coumarin anticoagulants. May lead to renal failure resulting in metformin accumulation w/ risk of lactic acidosis w/ iodinated contrast media. Decreased C_max & blood AUC of glyburide. Concomitant use w/ other drugs that may cause hyperglycemia & may exacerbate loss of glycemic control in diabetic patients including thiazides & other diuretics, corticosteroids, phenothiazines, thyroid products, estrogens, OCs, phenytoin, nicotinic acid, sympathomimetics, Ca channel blockers, & INH.

Antidiabetic Agents

A10BA02 - metformin ; Belongs to the class of biguanides. Used in the treatment of diabetes.

Rx