Repaglinide/Metformin Hydrochloride

Pronunciation: (reh-PAG-li-nide/met-FORE-min HYE-droe-KLOR-ide)Class: Antidiabetic combination

Trade Names:PrandiMet- Tablets repaglinide 1 mg/metformin 500 mg- Tablets repaglinide 2 mg/metformin 500 mg

Indications and Usage

Adjunct to diet and exercise to improve glycemic control in adult patients with type 2 diabetes who are already treated with a meglitinide (eg, repaglinide) and metformin or who have inadequate glycemic control on a meglitinide alone or metformin alone.

Contraindications

Renal function impairment (eg, serum creatinine levels of 1.5 mg/dL or higher in men, 1.4 mg/dL or higher in women, or abnormal CrCl); acute or chronic metabolic acidosis, including diabetic ketoacidosis; coadministration of both gemfibrozil and itraconazole; known hypersensitivity to any component of the product.

Dosage and Administration

Starting dose is based on the patient's current regimen, drug effectiveness, and tolerability.

Patients Inadequately Controlled With Metformin MonotherapyAdults

PO Start with repaglinide 1 mg/metformin 500 mg twice daily with meals and gradually increase the dose (based on glycemic control) to reduce the risk of hypoglycemia with repaglinide.

Patients Inadequately Controlled With Meglitinide MonotherapyAdults

PO Start with 500 mg of the metformin component of repaglinide/metformin twice daily and gradually increase the dose (based on glycemic control) to reduce the GI adverse reactions associated with metformin.

Patients Currently Taking Repaglinide and Metformin ConcomitantlyAdults

PO Start with the doses of repaglinide and metformin similar to, but not exceeding, the current doses, then titrate to the maximum daily dose necessary to achieve glycemic control.

General Advice

  • May be administered 2 to 3 times daily up to a max daily dose of repaglinide 10 mg/metformin 2,500 mg.
  • No more than repaglinide 4 mg/metformin 1,000 mg should be taken per meal.
  • The timing of the dose may vary from immediately preceding the meal to up to 30 min before the meal; however, within 15 min prior to the meal is preferable.

Storage/Stability

Do not store above 77°F. Protect from moisture.

Drug Interactions

Alcohol

The effect of metformin on lactate metabolism may be potentiated.

Cationic drugs (eg, amiloride, cimetidine, digoxin, morphine, procainamide, quinidine, quinine, ranitidine, triamterene, trimethoprim, vancomycin)

May increase metformin serum concentrations by competing for tubular secretion.

CYP2C8 inducers (eg, rifampin), CYP3A4 inducers (eg, rifampin)

Repaglinide serum concentrations may be reduced, decreasing the efficacy.

CYP2C8 inhibitors (eg, gemfibrozil, trimethoprim), CYP3A4 inhibitors (eg, clarithromycin, cyclosporine, grapefruit juice, itraconazole, ketoconazole, telithromycin)

Repaglinide serum concentrations may be elevated, increasing the pharmacologic effect and adverse reactions. Repaglinide is contraindicated in patients taking both gemfibrozil and itraconazole.

Drugs that cause hyperglycemia (eg, corticosteroids, diazoxide, diuretics, phenothiazines, phenytoin)

May increase blood glucose, interfering with glycemic control.

Drugs that cause hypoglycemia (eg, aspirin)

May decrease blood glucose, interfering with glycemic control.

Insulin

Repaglinide is not indicated for use in combination with isophane (NPH) insulin.

Parenteral iodinated contrast material

Because of the increased risk of metformin-induced lactic acidosis, discontinue repaglinide/metformin at the time of or prior to the procedure, and withhold repaglinide/metformin for 48 h subsequent to the procedure and reinstate treatment only after renal function has been evaluated and found to be healthy.

Laboratory Test Interactions

None well documented.

Adverse Reactions

Except for postmarketing reactions, which were reported with repaglinide, the following adverse reactions were reported with combined use of repaglinide plus metformin.

CNS

Headache (22%).

Dermatologic

Alopecia, Stevens-Johnson syndrome (postmarketing).

GI

Diarrhea (19%); nausea (15%); pancreatitis (postmarketing).

Hematologic-Lymphatic

Hemolytic anemia, severe hepatic function impairment including hepatitis and jaundice (postmarketing).

Metabolic-Nutritional

Hypoglycemia (33%).

Respiratory

Respiratory tract infection (11%).

Precautions

Warnings

Lactic acidosis: Although rare, lactic acidosis can occur and be fatal in approximately 50% of cases, as a result of metformin accumulation (eg, renal function impairment), or with pathophysiologic conditions associated with tissue hypoperfusion and hypoxia. The risk of lactic acidosis increases with the degree of renal function impairment and the patient's age.

Monitor

Monitor blood glucose to determine therapeutic response. Monitor vitamin B 12 levels at 2- to 3-year intervals in patients at risk of deficiency. Initial and periodic monitoring of hematologic parameters, including hemoglobin, hematocrit, and RBC, and monitoring of renal function should be done annually.

Pregnancy

Category C .

Lactation

Undetermined.

Children

Safety and efficacy not established.

Elderly

Because aging is associated with reduced renal function, use with caution, titrating to establish the minimum dose for adequate glycemic control.

Renal Function

Risk of metformin accumulation and lactic acidosis increases with the degree of renal function impairment.

Hepatic Function

Hepatic function impairment has been associated with cases of lactic acidosis.

Clinical status changes

Promptly evaluate patients who develop laboratory abnormalities for clinical illness for evidence of ketoacidosis or lactic acidosis. Evaluation should include serum electrolytes and ketones, blood glucose, and, if indicated, blood pH, lactate, pyruvate, and metformin levels.

Hypoxic states

Promptly discontinue treatment in patients experiencing hypoxic states, which may result from CV collapse (shock) from events such as acute CHF or acute MI.

Loss of glucose control

Consider temporarily withholding therapy and administering insulin in patients who lose glycemic control as a result of fever, trauma, infection, or surgery.

Surgical procedures

Temporarily suspend therapy for any surgical procedure (except minor procedures not associated with restricted intake of food and fluids). Do not restart until oral intake has resumed and renal function has been evaluated as normal.

Vitamin B 12 levels

Metformin may interfere with vitamin B 12 absorption from the B 12 -intrinsic factor complex.

Overdosage

Symptoms

Metformin

Lactic acidosis.

Repaglinide

Diarrhea, dizziness, headache, severe hypoglycemic reactions with coma, seizures, or other neurological impairment.

Patient Information

  • Instruct patients to take drug with meals, usually within 15 min prior to the meal, but the timing can vary from immediately preceding the meal to up to 30 min before the meal.
  • Instruct patients that if a meal is skipped, to skip the dose of repaglinide/metformin for that missed meal.
  • Advise patients to immediately contact health care provider if unexplained hyperventilation, myalgia, malaise, unusual somnolence, or other nonspecific symptoms occur.
  • Advise patients to avoid excessive acute or chronic alcohol use.

Copyright © 2009 Wolters Kluwer Health.