Normax

Metformin hydrochloride.

Each uncoated extended release tablet contains: Metformin Hydrochloride USP 500 mg.
Excipients q.s.
Normax (Metformin hydrochloride extended release tablets USP) is oral antihyperglycemic drug used in the management of type 2 diabetes.
The chemical name is N,N-dimethylimidodicarbonimidic diamide hydrochloride. The empirical formula is C₄H₁₁N₅•HCl and the molecular weight is 165.63.
Excipients/Inactive Ingredients: Hypermellose, Carboxymethylcellulose Sodium, Methacrylic acid copolymer, Macrogol, Povidone, Magnesium stearate.

Pharmacology: Metformin Hydrochloride is an antihyperglycemic agent which improves glucose tolerance in NIDDM (Type 2 diabetes mellitus) subjects, lowering both basal postprandial plasma glucose. Its pharmacological mechanisms of action are different from those of sulfonylureas. Metformin decrease hepatic glucose production and improves insulin sensitivity (increases peripheral glucose uptake and utilization). Unlike sulfonylureas, Metformin does not produce hypoglycemia in either diabetic or non-diabetic subjects, and does not cause hyperinsulinemia. With Metformin therapy, insulin secretion remains unchanged while fasting insulin levels and day long plasma insulin levels may actually decrease.
Pharmacokinetics: Absorption and Bioavailability: Following a single oral dose of sustained release Metformin, C_max is achieved with a median value of 7 hours and range of 4 hours to 8 hours. After repeated administration of a sustained-release formulation, Metformin does not accumulate in plasma. Metformin increased by approximately 50% when given with food on C_max and T_max of Metformin.
Distribution: The apparent volume of distribution (V/F) of Metformin following single oral dose of 850 mg is 654 ± 358 L. Metformin is negligibly bound to plasma proteins. At usual clinical doses and dosing schedules, steady state plasma concentrations of Metformin are reached within 24-48 hours and are generally <1 mg/mL.
Metabolism and Elimination: Metformin is excreted unchanged in the urine, and does not undergo hepatic metabolism or biliary excretion. Renal clearance is approximately 3.5 times greater than creatinine clearance, which indicates that tubular secretion is the major route of Metformin elimination. Following oral administration, approximately 90% of the absorbed drug is eliminated via the renal route within the first 24 hours, with a plasma elimination half-life of approximately 4.18 hours.
Special Populations: Patients with type 2 diabetes and gender: There are no reported differences in pharmacokinetics of Metformin Hydrochloride between patients with type 2 diabetes and normal subjects when analyzed according to gender.
Renal insufficiency: In patients with decreased renal function (based on measured creatinine clearance), the plasma and blood half-life of Metformin Hydrochloride is prolonged and the renal clearance is decreased in proportion to the decrease in creatinine clearance. This increased level of Metformin may lead to condition of lactic acidosis.
Hepatic insufficiency: No pharmacokinetic studies of Metformin Hydrochloride have been conducted in patients with hepatic insufficiency.
Geriatrics: Reported data from controlled pharmacokinetic studies of Metformin Hydrochloride in healthy elderly subjects suggest that total plasma clearance is decreased, the half-life is prolonged and C_max is increased, compared healthy young subjects. From this data, it appears that the change in Metformin Hydrochloride pharmacokinetics with aging is primarily accounted for by a change in renal function.
Pediatrics: No pharmacokinetic studies of Metformin Hydrochloride in pediatric patients have been conducted.

Metformin Hydrochloride (Normax) is used for treatment of non-insulin dependent diabetes mellitus (NIDDM) or type 2 DM, particularly in obese and juvenile diabetics in whom diet alone has failed as monotherapy, Metformin could also be used as adjunct to diet and exercise to improve glycemic control in patients with type II diabetes.

Dosage of Metformin Hydrochloride (Normax) must be individualized on the basis of both effectiveness and tolerance in patients. The maximum recommended daily dose of 2000 mg should not be exceeded.
The drug should be started at low dose, with gradual dose escalation, both to reduce gastrointestinal adverse effects and to permit identification of the minimum dose required for the adequate glycemic control of the patient. During treatment initiation and dose titration, fasting plasma glucose should be used to determine the therapeutic response to the drug and identify the minimum effective dose for the patient. Thereafter, glycosylated hemoglobin should be measured at intervals of approximately three months. The therapeutic goal should be to decrease both fasting plasma glucose and glycosylated hemoglobin levels to normal or near normal by using the lowest effective dose.
Short-term administration of the drug may be sufficient during periods of transient loss of blood glucose control in patients usually well-controlled on diet alone.
The usual starting dose of Metformin Hydrochloride (Normax) is 500 mg once daily with the evening meal. Dosage increase should be made in increments of 500 mg weekly, up to a maximum of 2000 mg once daily, trial of 1000 mg twice daily should be considered.
The tablet should be swallowed whole and not to be chewed. The tablet should be taken after meals, or as prescribed by a physician.

Hemodialysis may be used for the removal of accumulated drug from patients in whom Metformin Hydrochloride over dosage is suspected.

Renal or hepatic failure, alcoholism, NIDDM complicated by severe ketosis and acidosis, diabetic precoma and coma, patients undergoing surgery, after severe trauma or during infections, chronic obstructive pulmonary disease, coronary heart disease, cardiac failure, peripheral vascular disease, pregnancy, hypocalcemia and known hypersensitivity to Metformin.

Lactic acidosis is rare, but serious metabolic complication that can occur due to Metformin Hydrochloride accumulation. The reported incidence of lactic acidosis during Metformin Hydrochloride treatment is lower than 0.1 case per 1000 patient-years, and the mortality risk is even lower.
Lactic acidosis is a medical emergency that must be treated in a hospital setting. In a patient with lactic acidosis, the drug should be discontinued immediately and general supportive measures promptly instituted.

Adjust dose according to blood glucose levels during the first few months.
Use in Lactation: Studies have not been conducted in nursing mothers, but caution should be exercised in such patients, and a decision should be made to discontinue nursing or to discontinue the drug, taking into the account the importance of the drug to the mother.
Use in Children: Safety and effectiveness in children has not been established.
Use in Elderly: As aging is associated with reduced renal function, care should be taken in dose selection and should be based on careful and regular monitoring of renal functions.

Use in Lactation: Studies have not been conducted in nursing mothers, but caution should be exercised in such patients, and a decision should be made to discontinue nursing or to discontinue the drug, taking into the account the importance of the drug to the mother.

Gastrointestinal disturbances: Nausea, diarrhea, gastric pain, constipation, vomiting, metallic taste in the mouth.
Dermatological effects: rash, pruritus, urticaria, erythema, flushing.
Miscellaneous: headache and dizziness.
Impaired gastrointestinal absorption of Vitamin B12 and folic acid has been associated with long-term Metformin Hydrochloride therapy. However, if such symptoms occur, please consult the physician or pharmacist.

Drug interaction of Metformin Hydrochloride is seen with phenprocoumon, hyperglycemic agents (e.g. thiazides, corticosteroids), alcohol, furosemide, nifedipine and cationic drugs (amiloride, digoxin, morphine, procainamide, quinidine, quinine, ranitidine, triamterene, trimethoprim, cimetidine and vancomycin). Acarbose and guar gum may reduce the absorption of Metformin Hydrochloride.

Store at temperatures not exceeding 30°C. Protect from light and moisture.
Shelf Life: 36 months.

Antidiabetic Agents

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

Rx