SCITAG DUO 50/850MG

Indications

• Type 2 diabetes mellitus
• Gestational diabetes
• Management of pre-existing diabetes in pregnant women

Dosage

Children: For children aged 10 years and older, the usual starting dose is 500 mg taken with food, with gradual increases based on clinical response. Refer to the BNF for Children for specific dosing recommendations.

Adults: The initial dose is usually 500 mg to 1,000 mg taken orally with food, and the dosage may be gradually increased based on glycemic control and tolerance, with a maximum daily dose typically not exceeding 2,000 mg.

Mechanism of action

Metformin decreases hepatic glucose production and increases peripheral glucose utilization. It does not stimulate insulin release from the pancreas, making it antihyperglycemic rather than hypoglycemic. The drug also interacts with SIRT1, a protein involved in bile acid metabolism, contributing to its effects on glucose homeostasis.

Pharmacodynamics

Metformin improves glycemic control in patients with type 2 diabetes by reducing fasting and postprandial plasma glucose levels. It acts by decreasing intestinal absorption of glucose, increasing insulin sensitivity, and enhancing peripheral glucose uptake and utilization, without causing hypoglycemia.

Pharmacokinetics

Metformin is absorbed from the gastrointestinal tract and is excreted unchanged in the urine. It has a half-life of about 6 hours and does not undergo significant metabolism. The drug's pharmacokinetics can be affected by renal function, and caution is advised in patients with renal impairment.

Contra-indications

• Severe renal impairment (creatinine clearance less than 25 mL/minute)
• Acute or chronic metabolic acidosis, including diabetic ketoacidosis
• Hypersensitivity to metformin or any of its components

Adverse effects

• Nausea
• Vomiting
• Diarrhea
• Abdominal pain
• Lactic acidosis (rare)
• Hepatic disorders (rare)
• Oedema (rare)
• Acute generalised exanthematous pustulosis (very rare)
• Thrombocytopenia (very rare)

Interactions

• Angiotensin-converting enzyme inhibitors and angiotensin II receptor antagonists may require monitoring and adjustments
• Antacids containing magnesium and aluminium salts may reduce the absorption of metformin
• Concomitant use with other antihyperglycemic agents requires careful monitoring for hypoglycemia

Precautions

• Caution in patients with hepatic impairment
• Monitor liver function regularly during treatment
• Patients should be advised to discontinue use in the event of significant illness, especially dehydration or infections

Pregnancy

Avoid use during pregnancy. Women planning to become pregnant should discontinue metformin and consult a healthcare provider for safer alternatives.

Breast-feeding

Avoid use during breastfeeding. Metformin is excreted in breast milk, and its effects on a nursing infant are unknown.

Storage

Store in a cool, dry place, below 25°C. Protect from light.

Formulations

• Metformin hydrochloride 500 mg tablets
• Metformin hydrochloride 850 mg tablets
• Metformin hydrochloride 1000 mg tablets

Indications

• Induction of general anesthesia
• Maintenance of general anesthesia

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines.

Adults: For induction of anesthesia: Initially 0.5–1%, increased to a maximum of 8% based on patient response. For maintenance of anesthesia: Up to 50%, adjusted according to response.

Mechanism of action

Sevoflurane induces anesthesia by binding to ligand-gated ion channels and blocking central nervous system (CNS) neurotransmission. It enhances inhibitory postsynaptic channel activity through GABA_A and glycine receptors, while inhibiting excitatory synaptic activities via nicotinic acetylcholine, serotonin, and glutamate receptors. Sevoflurane modulates various ionic currents, impacting cardiac excitability and contractility.

Pharmacodynamics

Sevoflurane induces muscle relaxation and reduces tissue excitability, leading to a fast onset of action. It lowers the extent of gap junction-mediated cell-cell coupling, affecting the channels responsible for action potentials. Compared to other agents like halothane and isoflurane, it offers shorter emergence times and quicker onset of analgesia. However, it may increase risks of renal injury, respiratory depression, and QT prolongation, with notable adverse effects in pediatric populations.

Pharmacokinetics

Sevoflurane is rapidly absorbed and distributed due to its low blood solubility, allowing for swift equilibration between alveolar and arterial partial pressures. The drug is metabolized mainly in the liver, with minimal hepatic metabolism compared to other halogenated anesthetics. Its pharmacokinetic profile contributes to its rapid onset and recovery, making it suitable for outpatient procedures.

Contra-indications

• Known hypersensitivity to sevoflurane or any of its components
• Personal or family history of malignant hyperthermia
• Severe hepatic impairment

Adverse effects

• Drowsiness
• Fever
• Hypothermia
• Confusion
• Increased muscle rigidity
• Nephritis tubulointerstitial
• Abdominal distension
• Cardiac arrest
• Severe bradycardia
• Malignant hyperthermia
• Respiratory depression
• QT interval prolongation

Interactions

• Amfetamines (unknown additive effect)
• Sympathomimetics (unknown additive effect)

Precautions

• Use with caution in patients with a history of QT interval prolongation
• Monitor for respiratory depression and renal injury
• Assess plasma vitamin B12 concentration in at-risk patients
• Patients with Down Syndrome may have increased risk of severe bradycardia

Pregnancy

May depress neonatal respiration if used during delivery.

Breast-feeding

Breastfeeding can be resumed as soon as the mother has recovered sufficiently from anaesthesia.

Storage

Store at room temperature. Protect from light and moisture.

Formulations

• Sevoflurane volatile liquid 250 ml

Indications

• Type 2 diabetes mellitus as monotherapy if metformin is inappropriate
• Type 2 diabetes mellitus in combination with other antidiabetic drugs including insulin if glycemic control is not adequate with metformin alone

Dosage

Adults: 50 mg twice daily, or 100 mg once daily if used as monotherapy. In cases of renal impairment, reduce dose to 50 mg once daily.

Mechanism of action

Vildagliptin selectively inhibits the enzyme dipeptidyl peptidase-4 (DPP-4), which inactivates incretin hormones GLP-1 and GIP. By prolonging the half-life of these hormones, vildagliptin enhances insulin secretion in a glucose-dependent manner and reduces glucagon secretion. This leads to improved glucose homeostasis, reduction in fasting and postprandial glucose levels, and improved glycemic control in patients with type 2 diabetes mellitus.

Pharmacodynamics

Vildagliptin promotes glycemic control by increasing beta-cell sensitivity to glucose, enhancing glucose-dependent insulin secretion, and improving the insulin to glucagon ratio. It also decreases hepatic glucose production while having no effect on gastric emptying. Clinical studies have shown it effectively lowers glycated hemoglobin (HbA1c) and fasting plasma glucose levels in individuals with type 2 diabetes.

Pharmacokinetics

Vildagliptin is rapidly absorbed after oral administration, with peak plasma concentrations occurring within 1-2 hours. It has a half-life of approximately 2-3 hours. The drug is primarily excreted via the kidneys, with dose adjustments required for patients with renal impairment. It does not require adjustment for hepatic impairment. The pharmacokinetics may vary based on age and renal function.

Contra-indications

• History of pancreatitis
• Severe heart failure

Adverse effects

• Headache
• Dizziness
• Constipation
• Skin reactions
• Angioedema
• Back pain
• Cutaeous vasculitis
• Joint disorders
• Myalgia
• Acute pancreatitis
• Acute renal impairment
• Stevens-Johnson syndrome
• Vomiting

Interactions

• Dose of concomitant sulfonylurea or insulin may need to be reduced

Precautions

• Monitor renal function before treatment and periodically thereafter

Pregnancy

Avoid-toxicity in animal studies.

Breast-feeding

Avoid-present in milk in animal studies.

Storage

Store in a cool, dry place away from light.

Formulations

• Tablets: 50 mg
• Tablets: 100 mg

Indications

• Type 2 diabetes mellitus
• Polycystic ovary syndrome (PCOS)

Dosage

Children: The

Adults: The usual starting dose of metformin for adults is 500 mg taken orally twice a day or 850 mg once daily, with gradual increases based on tolerance and blood glucose levels. The maximum recommended daily dose is 2000-3000 mg, depending on the formulation used.

Mechanism of action

Metformin decreases blood glucose levels by decreasing hepatic glucose production (gluconeogenesis), decreasing intestinal absorption of glucose, and increasing insulin sensitivity, which enhances peripheral glucose uptake and utilization. It is known to inhibit mitochondrial complex I activity, leading to increased AMP:ATP ratios that activate AMP-activated protein kinase (AMPK), a key regulator of glucose metabolism. This activation results in reduced hepatic glucose output and improved cellular glucose uptake.

Pharmacodynamics

Metformin exerts its effects primarily by enhancing insulin sensitivity and reducing glucose production by the liver. Unlike sulfonylureas, which increase insulin secretion, metformin does not cause hyperinsulinemia. Its ability to lower fasting plasma glucose and glycosylated hemoglobin (HbA1c) levels makes it a cornerstone in the management of type 2 diabetes. Clinical studies have shown significant reductions in fasting plasma glucose and HbA1c levels in patients treated with metformin.

Pharmacokinetics

Metformin is absorbed from the gastrointestinal tract, with peak plasma concentrations typically occurring 2-3 hours after ingestion. It has a bioavailability of approximately 50-60% when administered orally. The drug is primarily eliminated unchanged by the kidneys, and its clearance is proportional to renal function. The half-life of metformin is about 6.5 hours. Accumulation may occur in cases of renal impairment, necessitating caution in patients with reduced renal function.

Adverse effects

• Gastrointestinal disturbances (nausea, vomiting, diarrhea)
• Lactic acidosis
• Vitamin B12 deficiency

Interactions

• dolutegravir+metformin: Moderate (increases exposure)
• cimetidine+metformin: Moderate (increases exposure)
• risdiplam+metformin: Moderate (increases concentration)
• vandetanib+metformin: Moderate (increases exposure)
• bictegravir+metformin: Unknown (increases exposure)
• guanfacine+metformin: Unknown (increases concentration)
• mexiletine+metformin: Unknown (affects exposure)
• pitolisant+metformin: Unknown (increases exposure)
• ribociclib+metformin: Unknown (increases exposure)

Precautions

• Renal impairment
• Dehydration
• Excessive alcohol intake

Pregnancy

Metformin is classified as a Category B medication. It is often used during pregnancy for managing gestational diabetes but should be administered under medical supervision.

Breast-feeding

Metformin is excreted in breast milk, but is generally considered safe for use during breastfeeding. Consult with a healthcare provider for specific guidance.

Storage

Store in a cool, dry place, away from direct light. Keep out of reach of children.

Formulations

• Tablets
• Extended-release tablets
• Oral solution

Mechanism of action

Metformin is widely used to treat hyperglycemia. However, metformin treatment may induce intrahepatic cholestasis and liver injury in a few patients with type II diabetes through an unknown mechanism. Here we show that metformin decreases SIRT1 protein levels in primary hepatocytes and liver. Both metformin-treated wild-type C57 mice and hepatic SIRT1-mutant mice had increased hepatic and serum bile acid levels. However, metformin failed to change systemic bile acid levels in hepatic SIRT1-mutant mice. Molecular mechanism study indicates that SIRT1 directly interacts with and deacetylates Foxa2 to inhibit its transcriptional activity on expression of genes involved in bile acids synthesis and transport. Hepatic SIRT1 mutation elevates Foxa2 acetylation levels, which promotes Foxa2 binding to and activating genes involved in bile acids metabolism, impairing hepatic and systemic bile acid homeostasis. Our data clearly suggest that hepatic SIRT1 mediates metformin effects on systemic bile acid metabolism and modulation of SIRT1 activity in liver may be an attractive approach for treatment of bile acid-related diseases such as cholestasis. Metformin is antihyperglycemic, not hypoglycemic. It does not cause insulin release from the pancreas and does not cause hypoglycemia, even in large doses. Metformin has no significant effects on the secretion of glucagon, cortisol, growth hormone or somatostatin. Metformin reduces glucose levels primarily by decreasing hepatic glucose production and by increasing insulin action in muscle and fat. ... May decrease plasma glucose by reducing the absorption of glucose from the intestine. /Salt not specified/ Metformin potentiates the effect of insulin by mechanisms not fully understood. Metformin does not stimulate pancreatic beta cells to increase secretion of insulin; insulin secretion must be present for metformin to work properly. It is postulated that metformin decreases hepatic glucose production and improves insulin sensitivity by increasing peripheral glucose uptake and utilization. /Salt not specified/ People with Type 2 diabetes mellitus (T2DM) have reduced bone mineral density and an increased risk of fractures due to altered mesenchymal stem cell (MSC) differentiation in the bone marrow. This leads to a shift in the balance of differentiation away from bone formation (osteogenesis) in favour of fat cell development (adipogenesis). The commonly used anti-diabetic drug, metformin, activates the osteogenic transcription factor Runt-related transcription factor 2 (Runx2), which may suppress adipogenesis, leading to improved bone health. Here we investigate the involvement of the metabolic enzyme, AMP-activated protein kinase (AMPK), in these protective actions of metformin. The anti-adipogenic actions of metformin were observed in multipotent C3H10T1/2 MSCs, in which metformin exerted reciprocal control over the activities of Runx2 and the adipogenic transcription factor, PPARgamma, leading to suppression of adipogenesis. These effects appeared to be independent of AMPK activation but rather through the suppression of the mTOR/p70S6K signalling pathway. Basal AMPK and mTOR/p70S6K activity did appear to be required for adipogenesis, as demonstrated by the use of the AMPK inhibitor, compound C. This observation was further supported by using AMPK knockout mouse embryo fibroblasts (MEFs) where adipogenesis, as assessed by reduced lipid accumulation and expression of the adipogeneic transcription factor, C/EBPbeta, was found to display an absolute requirement for AMPK. Further activation of AMPK in wild type MEFS, with either metformin or the AMPK-specific activator, A769662, was also associated with suppression of adipogenesis. It appears, therefore, that basal AMPK activity is required for adipogenesis and that metformin can inhibit adipogenesis through AMPK-dependent or -independent mechanisms, depending on the cellular context.

Mechanism of action

The precise mechanism of action of sevoflurane has not been fully elucidated. Like other halogenated inhalational anesthetics, sevoflurane induces anesthesia by binding to ligand-gated ion channels and blocking CNS neurotransmission. It has been suggested that inhaled anesthetics enhance inhibitory postsynaptic channel activity by binding GABA_A and glycine receptors, and inhibit excitatory synaptic channel activity by binding nicotinic acetylcholine, serotonin, and glutamate receptors. Sevoflurane has an effect on several ionic currents, including the hyperpolarisation-activated cation current (I_f), the T-type and L-type Ca²⁺ currents (I_{Ca, T} and I_{Ca, L}), the slowly activating delayed rectifier K⁺ currents (I_Ks), and the Na⁺/Ca²⁺ exchange current (I_NCX). This ability to modulate ion channel activity can also regulate cardiac excitability and contractility. Sevoflurane is widely used as a volatile anesthetic in clinical practice. However, its mechanism is still unclear. ...It has been reported that voltage-gated sodium channels have important roles in anesthetic mechanisms. Much attention has been paid to the effects of sevoflurane on voltage-dependent sodium channels. To elucidate this, /investigators/ examined the effects of sevoflurane on Na(v) 1.8, Na(v) 1.4, and Na(v) 1.7 expressed in Xenopus oocytes. The effects of sevoflurane on Na(v) 1.8, Na(v) 1.4, and Na(v) 1.7 sodium channels were studied by an electrophysiology method using whole-cell, two-electrode voltage-clamp techniques in Xenopus oocytes. Sevoflurane at 1.0 mM inhibited the voltage-gated sodium channels Na(v)1.8, Na(v)1.4, and Na(v)1.7, but sevoflurane (0.5 mM) had little effect. This inhibitory effect of 1 mM sevoflurane was completely abolished by pretreatment with protein kinase C (PKC) inhibitor, bisindolylmaleimide I. Sevoflurane appears to have inhibitory effects on Na(v)1.8, Na(v)1.4, and Na(v) 1.7 by PKC pathways. However, these sodium channels might not be related to the clinical anesthetic effects of sevoflurane. Sevoflurane has been demonstrated to vasodilate the feto-placental vasculature. /Investigators/ aimed to determine the contribution of modulation of potassium and calcium channel function to the vasodilatory effect of sevoflurane in isolated human chorionic plate arterial rings. Quadruplicate ex vivo human chorionic plate arterial rings were used in all studies. Series 1 and 2 examined the role of the K+ channel in sevoflurane-mediated vasodilation. Separate experiments examined whether tetraethylammonium, which blocks large conductance calcium activated K+ (KCa++) channels (Series 1A+B) or glibenclamide, which blocks the ATP sensitive K+ (KATP) channel (Series 2), modulated sevoflurane-mediated vasodilation. Series 3 - 5 examined the role of the Ca++ channel in sevoflurane induced vasodilation. Separate experiments examined whether verapamil, which blocks the sarcolemmal voltage-operated Ca++ channel (Series 3), SK&F 96365 an inhibitor of sarcolemmal voltage-independent Ca++ channels (Series 4A+B), or ryanodine an inhibitor of the sarcoplasmic reticulum Ca++ channel (Series 5A+B), modulated sevoflurane-mediated vasodilation. Sevoflurane produced dose dependent vasodilatation of chorionic plate arterial rings in all studies. Prior blockade of the KCa++ and KATP channels augmented the vasodilator effects of sevoflurane. Furthermore, exposure of rings to sevoflurane in advance of TEA occluded the effects of TEA. Taken together, these findings suggest that sevoflurane blocks K+ channels. Blockade of the voltage-operated Ca++channels inhibited the vasodilator effects of sevoflurane. In contrast, blockade of the voltage-independent and sarcoplasmic reticulum Ca++channels did not alter sevoflurane vasodilation. Sevoflurane appears to block chorionic arterial KCa++ and KATP channels. Sevoflurane also blocks voltage-operated calcium channels,

Pharmacodynamics

Sevoflurane induces muscle relaxation and reduces sensitivity by altering tissue excitability with a fast onset of action. It does so by decreasing the extent of gap junction-mediated cell-cell coupling and altering the activity of the channels that underlie the action potential. Compared to [halothane] and [isoflurane], sevoflurane has a shorter emergence time, as well as a shorter time to first analgesia. To reach an equilibrium between alveolar and arterial partial pressure, only a minimal amount of sevoflurane needs to be dissolved in blood. The use of sevoflurane can increase the risk of renal injury, respiratory depression, and QT prolongation. Also, it can lead to malignant hyperthermia, perioperative hyperkalemia, and pediatric neurotoxicity. Episodes of severe bradycardia and cardiac arrest have been reported in pediatric patients with Down Syndrome given sevoflurane. Sevoflurane anesthesia may impair the performance of activities requiring mental alertness, such as driving or operating machinery.

Mechanism of action

Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) are incretin hormones that regulate blood glucose levels and maintain glucose homeostasis. It is estimated that the activity of GLP-1 and GIP contribute more than 70% to the insulin response to an oral glucose challenge. They stimulate insulin secretion in a glucose-dependent manner via G-protein-coupled GIP and GLP-1 receptor signalling. In addition to their effects on insulin secretion, GLP-1 is also involved in promoting islet neogenesis and differentiation, as well as attenuating pancreatic beta-cell apoptosis. Incretin hormones also exert extra-pancreatic effects, such as lipogenesis and myocardial function. In type II diabetes mellitus, GLP-1 secretion is impaired, and the insulinotropic effect of GIP is significantly diminished. Vildagliptin exerts its blood glucose-lowering effects by selectively inhibiting dipeptidyl peptidase-4 (DPP-4), an enzyme that rapidly truncates and inactivates GLP-1 and GIP upon their release from the intestinal cells. DPP-4 cleaves oligopeptides after the second amino acid from the N-terminal end. Inhibition of DPP-4 substantially prolongs the half-life of GLP-1 and GIP, increasing the levels of active circulating incretin hormones. The duration of DPP-4 inhibition by vildagliptin is dose-dependent. Vildagliptin reduces fasting and prandial glucose and HbA1c. It enhances the glucose sensitivity of alpha- and beta-cells and augments glucose-dependent insulin secretion. Fasting and postprandial glucose levels are decreased, and postprandial lipid and lipoprotein metabolism are also improved.

Pharmacodynamics

Vildagliptin works to improve glycemic control in type II diabetes mellitus by enhancing the glucose sensitivity of beta-cells (β-cells) in pancreatic islets and promoting glucose-dependent insulin secretion. Increased GLP-1 levels leads to enhanced sensitivity of alpha cells to glucose, promoting glucagon secretion. Vildagliptin causes an increase in the insulin to glucagon ratio by increasing incretin hormone levels: this results in a decrease in fasting and postprandial hepatic glucose production. Vildagliptin does not affect gastric emptying. It also has no effects on insulin secretion or blood glucose levels in individuals with normal glycemic control. In clinical trials, treatment with vildagliptin 50-100 mg daily in patients with type 2 diabetes significantly improved markers of beta-cells, proinsulin to insulin ratio, and measures of beta-cell responsiveness from the frequently-sampled meal tolerance test. Vildagliptin has improves glycated hemoglobin (HbA1c) and fasting plasma glucose (FPG) levels.

Mechanism of action

Metformin's mechanisms of action are unique from other classes of oral antihyperglycemic drugs. Metformin decreases blood glucose levels by decreasing hepatic glucose production (also called gluconeogenesis), decreasing the intestinal absorption of glucose, and increasing insulin sensitivity by increasing peripheral glucose uptake and utilization. It is well established that metformin inhibits mitochondrial complex I activity, and it has since been generally postulated that its potent antidiabetic effects occur through this mechanism. The above processes lead to a decrease in blood glucose, managing type II diabetes and exerting positive effects on glycemic control. After ingestion, the organic cation transporter-1 (OCT1) is responsible for the uptake of metformin into hepatocytes (liver cells). As this drug is positively charged, it accumulates in cells and in the mitochondria because of the membrane potentials across the plasma membrane as well as the mitochondrial inner membrane. Metformin inhibits mitochondrial complex I, preventing the production of mitochondrial ATP leading to increased cytoplasmic ADP:ATP and AMP:ATP ratios. These changes activate AMP-activated protein kinase (AMPK), an enzyme that plays an important role in the regulation of glucose metabolism. Aside from this mechanism, AMPK can be activated by a lysosomal mechanism involving other activators. Following this process, increases in AMP:ATP ratio also inhibit _fructose-1,6-bisphosphatase_ enzyme, resulting in the inhibition of gluconeogenesis, while also inhibiting _adenylate cyclase_ and decreasing the production of cyclic adenosine monophosphate (cAMP), a derivative of ATP used for cell signaling. Activated AMPK phosphorylates two isoforms of acetyl-CoA carboxylase enzyme, thereby inhibiting fat synthesis and leading to fat oxidation, reducing hepatic lipid stores and increasing liver sensitivity to insulin. In the intestines, metformin increases anaerobic glucose metabolism in enterocytes (intestinal cells), leading to reduced net glucose uptake and increased delivery of lactate to the liver. Recent studies have also implicated the gut as a primary site of action of metformin and suggest that the liver may not be as important for metformin action in patients with type 2 diabetes. Some of the ways metformin may play a role on the intestines is by promoting the metabolism of glucose by increasing glucagon-like peptide I (GLP-1) as well as increasing gut utilization of glucose. In addition to the above pathway, the mechanism of action of metformin may be explained by other ways, and its exact mechanism of action has been under extensive study in recent years. Metformin is widely used to treat hyperglycemia. However, metformin treatment may induce intrahepatic cholestasis and liver injury in a few patients with type II diabetes through an unknown mechanism. Here we show that metformin decreases SIRT1 protein levels in primary hepatocytes and liver. Both metformin-treated wild-type C57 mice and hepatic SIRT1-mutant mice had increased hepatic and serum bile acid levels. However, metformin failed to change systemic bile acid levels in hepatic SIRT1-mutant mice. Molecular mechanism study indicates that SIRT1 directly interacts with and deacetylates Foxa2 to inhibit its transcriptional activity on expression of genes involved in bile acids synthesis and transport. Hepatic SIRT1 mutation elevates Foxa2 acetylation levels, which promotes Foxa2 binding to and activating genes involved in bile acids metabolism, impairing hepatic and systemic bile acid homeostasis. Our data clearly suggest that hepatic SIRT1 mediates metformin effects on systemic bile acid metabolism and modulation of SIRT1 activity in liver may be an attractive approach for treatment of bile acid-related diseases such as cholestasis. Metformin is antihyperglycemic, not hypoglycemic. It does not cause insulin release from the pancreas and does not cause hypoglycemia, even in large doses. Me

Pharmacodynamics

**General effects** Insulin is an important hormone that regulates blood glucose levels. Type II diabetes is characterized by a decrease in sensitivity to insulin, resulting in elevations in blood glucose when the pancreas can no longer compensate. In patients diagnosed with type 2 diabetes, insulin is unable to exert adequate effects on tissues and cells (i.e. insulin resistance) and insulin deficiency may also be present. Metformin reduces hepatic production of glucose, decreases the intestinal absorption of glucose, and enhances insulin sensitivity by increasing both peripheral glucose uptake and utilization. In contrast with drugs of the sulfonylurea class, which lead to hyperinsulinemia, the secretion of insulin is unchanged with metformin use. **Effect on fasting plasma glucose (FPG) and Glycosylated hemoglobin (HbA1c)** HbA1c is an important periodic measure of glycemic control used to monitor diabetic patients. Fasting plasma glucose is also a useful and important measure of glycemic control. In a 29-week clinical trial of subjects diagnosed with type II diabetes, metformin decreased the fasting plasma glucose levels by an average of 59 mg/dL from baseline, compared to an average increase of 6.3 mg/dL from baseline in subjects taking a placebo. Glycosylated hemoglobin (HbA1c) was decreased by about 1.4% in subjects receiving metformin, and increased by 0.4% in subjects receiving placebo only.