Product Information
Registration Status: ActiveGLUCOVANCE TABLET 500mg/5mg is approved to be sold in Singapore with effective from 2003-06-23. It is marketed by MERCK PTE LTD, with the registration number of SIN12322P.
This product contains Glibenclamide 5mg, and Metformin 500mg in the form of TABLET, FILM-COATED. It is approved for ORAL use.
This product is manufactured by MERCK SANTE SAS in FRANCE.
It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.
Description
Glyburide is an oral antihyperglycemic agent used for the treatment of non-insulin-dependent diabetes mellitus (NIDDM). It belongs to the sulfonylurea class of insulin secretagogues, which act by stimulating β cells of the pancreas to release insulin. Sulfonylureas increase both basal insulin secretion and meal-stimulated insulin release. Medications in this class differ in their dose, rate of absorption, duration of action, route of elimination and binding site on their target pancreatic β cell receptor. Sulfonylureas also increase peripheral glucose utilization, decrease hepatic gluconeogenesis and may increase the number and sensitivity of insulin receptors. Sulfonylureas are associated with weight gain, though less so than insulin. Due to their mechanism of action, sulfonylureas may cause hypoglycemia and require consistent food intake to decrease this risk. The risk of hypoglycemia is increased in elderly, debilitated and malnourished individuals. Glyburide has been shown to decrease fasting plasma glucose, postprandial blood glucose and glycosolated hemoglobin (HbA1c) levels (reflective of the last 8-10 weeks of glucose control). Glyburide appears to be completely metabolized, likely in the liver. Although its metabolites exert a small hypoglycemic effect, their contribution to glyburide's hypoglycemic effect is thought to be clinically unimportant. Glyburide metabolites are excreted in urine and feces in approximately equal proportions.
Indication
Indicated as an adjunct to diet to lower the blood glucose in patients with NIDDM whose hyperglycemia cannot be satisfactorily controlled by diet alone.
Mechanism of Action
Sulfonylureas such as glyburide bind to ATP-sensitive potassium channels on the pancreatic cell surface, reducing potassium conductance and causing depolarization of the membrane. Depolarization stimulates calcium ion influx through voltage-sensitive calcium channels, raising intracellular concentrations of calcium ions, which induces the secretion, or exocytosis, of insulin.
Pharmacokinetics
- Absorption
- Significant absorption within 1 hour and peak plasma levels are reached in 2 to 4 hours. Onset of action occurs within one hour.
- Distribution
- Steady state Vd=0.125 L/kg; Vd during elimination phase=0.155 L/kg.
- Metabolism
- Primarily hepatic (mainly cytochrome P450 3A4). The major metabolite is the 4-trans-hydroxy derivative. A second metabolite, the 3-cis-hydroxy derivative, also occurs. These metabolites do not contribute clinically significant hypoglycemic action in humans as they are only weakly active; however, retention of 4-trans-hydroxyglyburide may prolong the hypoglycemic effect of the agent in those with severe renal impairment.
- Elimination
Clearance
78 ml/hr/kg in healthy adults. Clearance may be substantially decreased in those with severe renal impairment.
Toxicity
Oral rat LD50: > 20,000 mg/kg. Oral mouse LD50: 3250 mg/kg.
Active Ingredient/Synonyms
1-((p-(2-(5-chloro-o-anisamido)ethyl)phenyl)sulfonyl)-3-cyclohexylurea | 1-(p-(2-(5-chloro-2-methoxybenzamido)ethyl)benzenesulfonyl)-3-cyclohexylurea | 5-chloro-N-(2-(4-((((cyclohexylamino)carbonyl)amino)sulfonyl)phenyl)ethyl)-2-methoxybenzamide | Glibenclamida | Glibenclamide | Glibenclamidum | Glyburide |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.
Description
Metformin is a biguanide antihyperglycemic agent used for treating non-insulin-dependent diabetes mellitus (NIDDM). It improves glycemic control by decreasing hepatic glucose production, decreasing glucose absorption and increasing insulin-mediated glucose uptake. Metformin may induce weight loss and is the drug of choice for obese NIDDM patients. Use of metformin is associated with modest weight loss. When used alone, metformin does not cause hypoglycemia; however, it may potentiate the hypoglycemic effects of sulfonylureas and insulin. Its main side effects are dyspepsia, nausea and diarrhea. Dose titration and/or use of smaller divided doses may decrease side effects. Metformin should be avoided in those with severely compromised renal function (creatinine clearance < 30 ml/min), acute/decompensated heart failure, severe liver disease and for 48 hours after the use of iodinated contrast dyes due to the risk of lactic acidosis. Lower doses should be used in the elderly and those with decreased renal function. Metformin decreases fasting plasma glucose, postprandial blood glucose and glycosolated hemoglobin (HbA1c) levels, which are reflective of the last 8-10 weeks of glucose control. Metformin may also have a positive effect on lipid levels. In 2012, a combination tablet of linagliptin plus metformin hydrochloride was marketed under the name Jentadueto for use in patients when treatment with both linagliptin and metformin is appropriate.
Indication
For use as an adjunct to diet and exercise in adult patients (18 years and older) with NIDDM. May also be used for the management of metabolic and reproductive abnormalities associated with polycystic ovary syndrome (PCOS). Jentadueto is for the treatment of patients when both linagliptin and metformin is appropriate.
Mechanism of Action
Metformin's mechanisms of action differ from other classes of oral antihyperglycemic agents. Metformin decreases blood glucose levels by decreasing hepatic glucose production, decreasing intestinal absorption of glucose, and improving insulin sensitivity by increasing peripheral glucose uptake and utilization. These effects are mediated by the initial activation by metformin of AMP-activated protein kinase (AMPK), a liver enzyme that plays an important role in insulin signaling, whole body energy balance, and the metabolism of glucose and fats. Activation of AMPK is required for metformin's inhibitory effect on the production of glucose by liver cells. Increased peripheral utilization of glucose may be due to improved insulin binding to insulin receptors. Metformin administration also increases AMPK activity in skeletal muscle. AMPK is known to cause GLUT4 deployment to the plasma membrane, resulting in insulin-independent glucose uptake. The rare side effect, lactic acidosis, is thought to be caused by decreased liver uptake of serum lactate, one of the substrates of gluconeogenesis. In those with healthy renal function, the slight excess is simply cleared. However, those with severe renal impairment may accumulate clinically significant serum lactic acid levels. Other conditions that may precipitate lactic acidosis include severe hepatic disease and acute/decompensated heart failure.
Pharmacokinetics
- Absorption
- Absorbed over 6 hours, bioavailability is 50 to 60% under fasting conditions. Administration with food decreases and delays absorption. Some evidence indicates that the level of absorption is not dose-related, suggesting that absorption occurs through a saturable process. Limited data from animal and human cell cultures indicate that absorption occurs through a passive, non-saturable process, possibly involving a paracellular route. Peak action occurs 3 hours after oral administration.
- Distribution
- 654 L for metformin 850 mg administered as a single dose. The volume of distribution following IV administration is 63-276 L, likely due to less binding in the GI tract and/or different methods used to determine volume of distribution.
- Metabolism
- Metformin is not metabolized.
- Elimination
Clearance
718-1552 mL/minute following single oral dose of 0.5-1.5 g. Metformin is removed by hemodialysis at a rate of approximately 170 ml/min under good hemodynamic conditions.
Toxicity
Acute oral toxicity (LD50): 350 mg/kg [Rabbit]. It would be expected that adverse reactions of a more intense character including epigastric discomfort, nausea, and vomiting followed by diarrhea, drowsiness, weakness, dizziness, malaise and headache might be seen.
Active Ingredient/Synonyms
1,1-Dimethylbiguanide | Dimethylbiguanid | Metformin | Metformina | Metformine | Metforminum | Metformin |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.