Lactic acidosis is a rare, but serious, metabolic complication that can occur due to metformin accumulation during treatment with GLUCOVANCE; 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 µg/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 and by use of the minimum effective dose of metformin. In particular, treatment of the elderly should be accompanied by careful monitoring of renal function. GLUCOVANCE 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, GLUCOVANCE 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, GLUCOVANCE 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 GLUCOVANCE, since alcohol potentiates the effects of metformin hydrochloride on lactate metabolism. In addition, GLUCOVANCE 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). GLUCOVANCE 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 GLUCOVANCE, gastrointestinal symptoms, which are common during initiation of therapy with metformin, are unlikely to be drug related. Later occurrence of gastrointestinal symptoms could be due to lactic acidosis or other serious disease.
Levels of fasting venous plasma lactate above the upper limit of normal but less than 5 mmol/L in patients taking GLUCOVANCE do not necessarily indicate impending lactic acidosis and may be explainable by other mechanisms, such as poorly controlled diabetes or obesity, vigorous physical activity, or technical problems in sample handling. (See also PRECAUTIONS.)
Lactic acidosis should be suspected in any diabetic patient with metabolic acidosis lacking evidence of ketoacidosis (ketonuria and ketonemia).
Lactic acidosis is a medical emergency that must be treated in a hospital setting. In a patient with lactic acidosis who is taking GLUCOVANCE, the drug should be discontinued immediately and general supportive measures promptly instituted. Because metformin hydrochloride is dialyzable (with a clearance of up to 170 mL/min under good hemodynamic conditions), prompt hemodialysis is recommended to correct the acidosis and remove the accumulated metformin. Such management often results in prompt reversal of symptoms and recovery. (See also CONTRAINDICATIONS and PRECAUTIONS.)
(Glyburide and Metformin HCl Tablets)
1.25 mg/250 mg
2.5 mg/500 mg
5 mg/500 mg
GLUCOVANCE® (Glyburide and Metformin HCl Tablets) contains two oral antihyperglycemic drugs used in the management of type 2 diabetes, glyburide and metformin hydrochloride.
GLUCOVANCE is indicated as initial therapy, as an adjunct to diet and exercise, to improve glycemic control in patients with type 2 diabetes whose hyperglycemia cannot be satisfactorily managed with diet and exercise alone.
GLUCOVANCE is indicated as second-line therapy when diet, exercise, and initial treatment with a sulfonylurea or metformin do not result in adequate glycemic control in patients with type 2 diabetes. For patients requiring additional therapy, a thiazolidinedione may be added to GLUCOVANCE to achieve additional glycemic control.
Published Studies Related to Glucovance (Glyburide / Metformin)
Beta-cell response to metformin-glibenclamide combination tablets (Glucovance) in patients with type 2 diabetes. [2006.07]
This exploratory double-blind, randomised, 20-week study evaluated the mechanism of action of metformin-glibenclamide combination tablets (Glucovance) vs... Larger beta-cell responses between combination tablets and glibenclamide may reflect more rapid glibenclamide absorption.
Investigation of the pharmacokinetic and pharmacodynamic interactions between memantine and glyburide/metformin in healthy young subjects: a single-center, multiple-dose, open-label study. [2005.10]
BACKGROUND: The high prevalence rates of both Alzheimer's disease (AD) and type 2 diabetes mellitus in the elderly population suggest that concomitant pharmacotherapy is likely. Given the renal tubular transport and extensive urinary excretion of memantine and metformin, it was of interest to assess the pharmacokinetic and pharmacodynamic interaction with glyburide/metformin. OBJECTIVE: The primary goal of this study was to determine whether an in vivo pharmacokinetic or pharmacodynamic interaction exists between memantine (an uncompetitive, moderate-affinity, N-methyl-D-aspartate receptor antagonist with fast blocking/unblocking kinetics that is available in the United States for moderate to severe AD) and glyburide/metformin (a combination pharmacotherapy formulation approved for glycemic control in patients with type 2 diabetes mellitus)... CONCLUSIONS: No pharmacokinetic interactions between memantine and glyburide/metformin were detected in this study of healthy young volunteers. Memantine had no effect on the pharmacodynamic activities of glyburide and metformin, and the drug combination was well tolerated in this population.
PRESERVE-beta: two-year efficacy and safety of initial combination therapy with nateglinide or glyburide plus metformin. [2005.09]
CONCLUSIONS: Similar good glycemic control can be maintained for 2 years with either treatment regimen, but nateglinide/metformin may represent a safer approach to initial combination therapy.
Durable efficacy of metformin/glibenclamide combination tablets (Glucovance) during 52 weeks of open-label treatment in type 2 diabetic patients with hyperglycaemia despite previous sulphonylurea monotherapy. [2004.09]
Oral anti-diabetic combinations that address insulin resistance and beta-cell dysfunction (e.g... Metformin-glibenclamide combination tablets are an effective and well-tolerated therapeutic option for intensifying oral anti-diabetic therapy.
Glycemic control with glyburide/metformin tablets in combination with rosiglitazone in patients with type 2 diabetes: a randomized, double-blind trial. [2004.02.15]
PURPOSE: To assess the efficacy and safety of adding rosiglitazone to an established regimen of glyburide/metformin in patients with type 2 diabetes who had not achieved adequate glycemic control (glycosylated hemoglobin [HbA1C] levels >7.0% and < or =10.0%)... CONCLUSION: In patients with inadequate glycemic control despite established glyburide/metformin therapy, the addition of rosiglitazone improves glycemic control, allowing more patients to achieve an HbA1C level <7% and perhaps delaying the need for insulin treatment.
Clinical Trials Related to Glucovance (Glyburide / Metformin)
AVANDIA With Glyburide In African American And Hispanic Patients With Type 2 Diabetes Not Controlled by Glyburide Alone [Completed]
This study was designed to evaluate the safety and efficacy of AVANDIA (rosiglitazone) (8mg
once daily) in African American and Hispanic patients with type 2 diabetes mellitus. As
microvascular and macrovascular disease are significant contributors to diabetes morbidity
and mortality and previous studies suggest that the thiazolidinedione compounds could have
potentially beneficial vascular effects, the effects of rosiglitazone therapy on serum
parameters associated with endothelial dysfunction, vascular inflammation and impaired
fibrinolysis were examined in this study. Improvement in these parameters suggests that
rosiglitazone may provide an additional beneficial vascular effect, apart from its ability to
improve glycemic control.
Comparison of Glucovance to Insulin for Diabetes During Pregnancy [Recruiting]
Pregnant women with gestational or Type 2 diabetes who require medication are placed in one
of two groups: Insulin injections or Glucovance (oral administration). Blood glucose is
checked 5 times per day, and medication adjusted by perinatologist according to glucose
levels. The hypothesis is that patients will have similar or improved blood glucose control
on an oral agent as compared to control on insulin.
Glyburide Compared to Insulin in the Management of White's Classification A2 Gestational Diabetes [Recruiting]
The purpose of this study is to determine whether the oral administration of glyburide is as
effective as insulin in the treatment of gestational diabetes.
1. SYNOPSIS: Infants born to mothers with gestational diabetes(GDM) are at risk for a
variety of adverse perinatal outcomes including macrosomia with subsequent birth trauma
and cesarean delivery, neonatal hypoglycemia, polycythemia, jaundice, hypocalcemia,
respiratory depression and newborn intensive care unit admission. These adverse
outcomes are thought to be related to the degree of maternal hyperglycemia during
pregnancy. Women with GDM are typically treated with insulin to lower blood glucose
levels to as near-normal as possible. A single randomized trial has suggested that the
oral sulfonylurea, glyburide is a clinically effective and safe alternative to insulin
2. Many obstetric care providers have adopted the use of glyburide in the routine
management of gestational diabetes. The American College of Obstetrics and Gynecology
and the American Diabetic Association both state that further studies are needed in a
larger patient population before the use of newer oral hypoglycemic agents can be
supported for use in pregnancy.
3. STATUS: Previous studies have demonstrated that there is no maternal-fetal transfer of
glyburide and when compared to insulin is an effective alternative to insulin.
Additionally, a published cost analysis concluded that glyburide is significantly less
costly than insulin for the treatment of GDM. The benefits of an oral agent for the
management of gestational diabetes include less discomfort for the patient in drug
administration, lower requirement for patient education in the administration of
injectable medications and less chance of error in dosing. Our study population is
more ethnically diverse and our incidence of large for gestational age infants is lower
than in the largely Hispanic population studied by Langer et al. Many obstetricians,
including ourselves, apply different criteria than Langer for diagnosing gestational
diabetes , and for deciding when to institute insulin therapy. It is our goal to
confirm the prior single study concerning the safety and efficacy of glyburide in
reducing the complications of GDM utilizing a more ethnically diverse population with
more realistic goals in glycemic control. To this end we will add to the medical
literature supporting this alternative therapy to insulin.
A Drug-Drug Interaction Study of GK Activator (2) and Glyburide in Patients With Type 2 Diabetes. [Completed]
This study will assess the potential pharmacodynamic and potential pharmacokinetic
interaction between GK Activator (2) and glyburide, in type 2 diabetes patients not
adequately controlled with glyburide as standard prescribed therapy. Patients will enter the
study taking a dose of glyburide (10-20mg po daily) as prescribed prior to study start. GK
Activator (2) 100mg bid will be added for 5 days. From days 6-12 patients will receive GK
Activator (2) monotherapy, and from day 13 GK Activator (2) will be discontinued and
glyburide treatment re-started. The anticipated time on study treatment is <3 months, and the
target sample size is <100 individuals.
Sulfonylurea Effects on Glucagon Regulation During Hypoglycemia in Type 1 DM [Recruiting]
We aim to demonstrate that oral administration of glibenclamide stimulates pancreatic
glucagon secretion during hypoglycemia in insulin-deficient (C-peptide negative) patients
with type 1 diabetes when compared to type 1 diabetic patients with residual insulin
secretion (C-peptide positive).
Reports of Suspected Glucovance (Glyburide / Metformin) Side Effects
Hepatic Cirrhosis (5),
Lactic Acidosis (3),
Blood Glucose Increased (3),
Disseminated Intravascular Coagulation (2),
Multi-Organ Failure (2),
Renal Failure Acute (2),
Hepatic Fibrosis (2), more >>
Page last updated: 2007-05-02