Metformin-Teva, 850 mg 60 pcs

Metformin has hypoglycemic effect.

Pharmacodynamics

Metformin is an oral hypoglycemic agent of biguanide group. In patients with diabetes it decreases the concentration of glucose in blood by inhibiting gluconeogenesis in the liver, reducing the absorption of glucose from the gastrointestinal tract (GIT) and increasing its utilization in tissues by increasing their sensitivity to insulin (mainly in transverse striated musculature and to a lesser extent in adipose tissue).

It does not stimulate insulin secretion and does not cause hypoglycemic reactions. It influences lipid metabolism – decreases the concentration in the blood serum of triglycerides, cholesterol and low-density lipoproteins. Stimulates intracellular glycogenesis by activating glycogen synthase.

Pharmacokinetics

Intake
After oral administration metformin is fairly completely absorbed from the gastrointestinal tract. Absolute bioavailability is 50-60%. Maximal concentration (Cmax) in plasma is approximately 2 µg/ml or 15 µmol/L and is reached after 2.5 hours. After 7 hours, absorption from the gastrointestinal tract ends, and plasma concentration of metformin gradually decreases. When concomitant intake of food, absorption of metformin is reduced and slows down.

Distribution
Metformin is almost not bound to plasma proteins and is rapidly distributed to body tissues. It penetrates red blood cells. It accumulates in the salivary glands, liver and kidneys. The apparent volume of distribution is 63-276 liters.

Metabolism and excretion
Excreted by the kidneys unchanged. Clearance of metformin in healthy subjects is 400 ml/min, indicating active glomerular filtration and tubular secretion. The elimination half-life (T1/2) is approximately 6.5 h.

Pharmacokinetics in special clinical cases

In patients with renal impairment, metformin renal clearance decreases in proportion to decreased creatinine clearance, T1/2 increases, resulting in increased metformin blood concentrations. Cumulation is possible.

Indications

Type 2 diabetes mellitus in adults (especially in obese patients) when diet and exercise are ineffective as monotherapy or in combination with other oral hypoglycemic agents or insulin.

Active ingredient

Composition

Active substance:

metformin hydrochloride 850 mg;

Assisted substances:

povidone K30;

povidone K90;

colloidal silicon dioxide;

magnesium stearate;

coating Opadray white Y-1-7000H (hypromellose (E464);

titanium dioxide (E171);

macrogol 400

How to take, the dosage

Overly, during or immediately after a meal.

Monotherapy and combined therapy with other oral hypoglycemic agents

The initial dose is 500-1000 mg once daily in the evening. In 7-15 days with absence of adverse effects of gastrointestinal tract it is prescribed 500-1000 mg 2 times daily in the morning and in the evening. Further gradual dose increase depending on blood glucose concentration is possible.

The maintenance dose is 1500-2000 mg/day. To reduce gastrointestinal side effects, the dose should be divided into 2-3 doses. The maximum daily dose is 3000 mg/day in 3 doses.

Slowly increasing the dose may improve gastrointestinal tolerance of the drug.

Patients taking metformin at doses of 2000-3000 mg/day may be switched to a dose of 1000 mg. The maximum recommended dose is 3000 mg/day in 3 doses.

If therapy is switched from another hypoglycemic drug, the other drug should be discontinued and Metformin-Teva should be started at the dose indicated above.

Combinations with insulin

Metformin-Teva and insulin can be used as combination therapy to achieve better glycemic control.

The drug is given in the usual starting dose of 500 or 850 mg 2-3 times a day. The dose of insulin is adjusted on the basis of the results of blood glucose measurements. After 10-15 days, the dose is adjusted depending on the blood glucose concentration.

The maximum dose of metformin in combination therapy is 2 g/day in 2-3 doses.

In elderly patients, the daily dose should not exceed 1000 mg/day.

Interaction

Unrecommended combinations
Simultaneous use of metformin with danazol may result in hyperglycemic effects. If treatment with danazolol is necessary and after stopping its administration, metformin dose should be adjusted under glycemic control. Concomitant use of metformin with alcohol and ethanol-containing drugs increases the risk of lactoacidosis during acute alcohol intoxication, especially when fasting or following a low-calorie diet, as well as liver failure.

Combinations requiring special caution
Chlorpromazine at high doses (100 mg/day) reduces insulin release and increases blood glucose concentrations. When concomitant use with neuroleptics and after discontinuation of them, metformin dose adjustment is required under glycemic control. Glucocorticosteroids (GCS) decrease glucose tolerance and increase blood glucose concentration, in some cases causing ketosis. Metformin dose adjustment with glycemic control is required if such a combination is necessary and after discontinuation of GCS.

In concomitant use of loop diuretics and metformin there is a risk of lactoacidosis due to possible functional renal failure.

The radiological study with the use of iodine-containing radiopaque agents may cause lactocidosis in diabetic patients with a background of functional renal failure. Metformin administration should be discontinued 48 hours before and not resumed until 48 hours after radiological examination with contrast agents.

The administration in the form of beta2-adrenomimetic injections reduces hypoglycemic effect of metformin due to stimulation of beta2-adrenoreceptors. In this case, blood glucose concentration should be monitored and, if necessary, insulin should be prescribed. Angiotensin-converting enzyme inhibitors and other antihypertensive drugs may decrease the blood glucose concentration. If necessary, the dose of metformin should be adjusted.

In concomitant use of metformin with sulfonylurea derivatives, insulin, acarbose and salicylates may increase the hypoglycemic effect. “Loop” diuretics and nonsteroidal anti-inflammatory drugs (NSAIDs) increase the risk of reduced renal function. In this case, caution should be exercised when using metformin.

Special Instructions

During treatment with Metformin-Teva, blood glucose concentrations should be monitored regularly on an empty stomach and after meals.

The patient should be warned to stop taking the drug and seek medical attention if vomiting, abdominal pain, muscle pain, general weakness, and severe malaise occur. These symptoms may be a sign of incipient lactoacidosis. Metformin-Teva should be discontinued 48 hours before and within 48 hours after radiological examination (including urography, intravenous angiography) with radiopaque contrast agents.

The drug Metformin-Teva should be discontinued 48 hours before and 48 hours after surgical interventions under general anesthesia, spinal or peridural anesthesia. Because metformin is excreted by the kidneys, CK should be determined before treatment and regularly thereafter: in patients with preserved renal function once a year, in patients with reduced CK and in elderly patients 2-4 times a year.

Particular caution should be exercised if renal function is impaired, e.g., during initial therapy with antihypertensives, diuretics, NSAIDs.

Patients should be advised to seek medical attention if they have symptoms of bronchopulmonary infection or urinary tract infections. During the use of the drug Metformin-Teva it is necessary to refrain from taking alcohol due to the increased risk of hypoglycemia and disulfiram-like effect. Hypovitaminosis B12 when taking Metformin-Teva is due to impaired absorption of vitamin B12 and is reversible. When discontinuing the drug Metformin-Teva signs of hypovitaminosis B12 quickly disappear.

Contraindications

Side effects

Central nervous system disorders: often – taste disorders (metallic taste in the mouth).

Gastrointestinal system disorders: very common – nausea, vomiting, abdominal pain, lack of appetite, occurring during the initial treatment and in most cases” spontaneously passing; single cases – liver dysfunction or hepatitis, which completely disappear after discontinuation of the drug.

Allergic reactions: very rare – erythema, skin itching, rash.

Metabolic disorders: very common – lactoacidosis (requires discontinuation of the drug).

Others: very rare – with prolonged use hypovitaminosis B12 develops.

Overdose

Symptoms: When using metformin at a dose of 85 g, no hypoglycemia was observed, but the development of lactoacidosis was noted. Early symptoms of lactocidosis are nausea, vomiting, diarrhea, decreased body temperature, abdominal pain, muscle pain; further on, rapid breathing, dizziness, impaired consciousness and development of coma may be noted.

Treatment: In case of signs of lactocidosis the drug treatment should be stopped immediately, the patient should be urgently hospitalized and after determining the lactate concentration the diagnosis should be determined. The most effective measure for lactate and metformin elimination from the body is hemodialysis. Symptomatic treatment is also carried out.

Similarities