Analgin Bufus (Solution) Instructions for Use

Marketing Authorization Holder

Obnovlenie Pfc, JSC (Russia)

ATC Code

N02BB02 (Metamizole sodium)

Active Substance

Metamizole sodium (Rec.INN registered by WHO)

Dosage Form

Analgin Bufus

Solution for intravenous and intramuscular administration 1 g/2 ml: amp. 10 pcs.

Dosage Form, Packaging, and Composition

2 ml – ampoules (10) – cardboard boxes.

Clinical-Pharmacological Group

Analgesic-antipyretic

Pharmacotherapeutic Group

Non-narcotic analgesic agent

Pharmacological Action

Pyrazolone derivative. Metamizole sodium non-selectively blocks cyclooxygenase and reduces the formation of prostaglandins from arachidonic acid.

It impedes the conduction of extra- and proprioceptive pain impulses along the Gaulle and Burdach bundles, increases the excitability threshold of the thalamic pain sensitivity centers, and increases heat transfer.

A distinctive feature is the low severity of the anti-inflammatory effect. The action develops 20-40 minutes after oral administration and reaches a maximum after 2 hours.

It has analgesic, antipyretic, and some antispasmodic effects (on the smooth muscles of the urinary and biliary tracts).

Pharmacokinetics

After intravenous administration, the half-life is 14 minutes. Approximately 96% is excreted in the urine as metabolites.

The binding of the active metabolite to plasma proteins is 50-60%. It is metabolized in the liver and excreted by the kidneys.

In therapeutic doses, it penetrates into breast milk.

Indications

• Mild to moderate pain syndrome of various origins (headache; migraine; toothache; neuralgia; myalgia; dysmenorrhea; postoperative pain, in combination with the prescription of antispasmodic agents for renal, biliary, and intestinal colic);
• Febrile conditions in infectious and inflammatory diseases, insect bites, post-transfusion complications.

ICD codes

Dosage Regimen

The drug is administered intramuscularly or intravenously (for severe pain) at a dose of 1-2 ml of the 500 mg/ml solution 2-3 times a day, but not more than 2 g per day.

The maximum single dose is 1 g, the daily dose is 2 g.

For children, it is administered at a rate of 0.1-0.2 ml of the 500 mg/ml solution per every 10 kg of the child’s body weight 2-3 times a day.

For children under 1 year of age with a body weight of more than 5 kg, the drug is administered only intramuscularly, for a course not exceeding 3 days.

The administered solution should be at body temperature. Doses greater than 1 g should be administered intravenously.

Conditions for anti-shock therapy must be available. The most common cause of a sharp decrease in blood pressure is too high an injection rate, therefore intravenous administration should be carried out slowly (at a rate not exceeding 1 ml/min), with the patient in a “lying” position, under the control of blood pressure, heart rate, and respiratory rate.

With prolonged (more than a week) use of the drug, monitoring of the peripheral blood picture and the functional state of the liver is necessary.

Adverse Reactions

From the urinary system impaired renal function, oliguria, anuria, proteinuria, interstitial nephritis, red coloration of urine.

Allergic reactions skin rash, Quincke’s edema, urticaria (including on the conjunctiva and mucous membranes of the nasopharynx), angioedema, in rare cases – malignant exudative erythema (Stevens-Johnson syndrome), toxic epidermal necrolysis (Lyell’s syndrome), bronchospastic syndrome, anaphylactic shock.

From the hematopoietic organs agranulocytosis, leukopenia, thrombocytopenia.

Other decreased blood pressure.

Local reactions with intramuscular administration, infiltrates at the injection site are possible.

Contraindications

Hypersensitivity to pyrazolones, bone marrow depression (agranulocytosis, cytostatic or infectious neutropenia), hepatic and/or renal failure, anemia (including hereditary hemolytic anemia), bronchial asthma induced by the intake of acetylsalicylic acid, salicylates or other non-steroidal anti-inflammatory drugs, leukopenia, pregnancy (I and III trimesters), lactation period, children in the first three months of life, with a body weight of less than 5 kg.

It is unacceptable to use for the relief of acute abdominal pain (until the cause is clarified).

With caution. Pregnancy (II trimester), kidney diseases (pyelonephritis, glomerulonephritis – including in history), long-term ethanol abuse, intravenous administration to patients with systolic blood pressure below 100 mm Hg or with circulatory instability (for example, against the background of myocardial infarction, multiple trauma, incipient shock). Infant age under 3 months.

Use in Pregnancy and Lactation

Contraindicated in the I and III trimesters of pregnancy, during lactation. Use with caution in the II trimester of pregnancy.

Use in Hepatic Impairment

Contraindicated in hepatic failure.

Use in Renal Impairment

Contraindicated in renal failure. With caution in kidney diseases (pyelonephritis, glomerulonephritis – including in history).

Pediatric Use

Contraindicated in children in the first three months of life, with a body weight of less than 5 kg. With caution: infant age under 3 months. Treatment of children under 5 years of age only under medical supervision.

Special Precautions

When treating children under 5 years of age and patients receiving cytotoxic drugs, the intake of metamizole sodium should be carried out only under medical supervision.

Intolerance is very rare, however, the threat of anaphylactic shock after intravenous administration of the drug is relatively higher than after oral administration.

Patients with atopic bronchial asthma and hay fever have an increased risk of developing allergic reactions.

Against the background of taking metamizole sodium, the development of agranulocytosis is possible, therefore, if an unmotivated rise in temperature, chills, sore throat, difficulty swallowing, stomatitis are detected, as well as with the development of vaginitis or proctitis, immediate withdrawal of the drug is necessary.

With prolonged use, it is necessary to monitor the peripheral blood picture.

It is unacceptable to use for the relief of acute abdominal pain (until the cause is clarified). For intramuscular injection, a long needle must be used.

Red coloration of urine is possible due to the excretion of a metabolite (of no significance).

Overdose

Symptoms nausea, vomiting, gastralgia, oliguria, hypothermia, decreased blood pressure, tachycardia, shortness of breath, tinnitus, drowsiness, delirium, impaired consciousness, acute agranulocytosis, hemorrhagic syndrome, acute renal and/or hepatic failure, convulsions, paralysis of the respiratory muscles.

Treatment gastric lavage, saline laxatives, activated charcoal; forced diuresis, hemodialysis; with the development of a convulsive syndrome – intravenous administration of diazepam and fast-acting barbiturates.

Drug Interactions

Due to the high probability of pharmaceutical incompatibility, it should not be mixed with other drugs in the same syringe. It enhances the effects of ethanol.

Radiocontrast agents, colloidal blood substitutes, and penicillin should not be used during treatment with metamizole sodium.

With simultaneous use with cyclosporine, the concentration of the latter in the blood decreases.

Metamizole sodium, by displacing oral hypoglycemic drugs, indirect anticoagulants, glucocorticosteroids, and indomethacin from their binding to plasma proteins, increases their activity.

Phenylbutazone, barbiturates, and other inducers of microsomal liver enzymes, when prescribed simultaneously, reduce the effectiveness of metamizole sodium.

Simultaneous use with other non-narcotic analgesics, tricyclic antidepressants, contraceptive hormonal drugs, and allopurinol can lead to increased toxicity.

Sedative and anxiolytic drugs (tranquilizers) enhance the analgesic effect of metamizole sodium.

Thiamazole and cytostatics increase the risk of leukopenia.

The effect is enhanced by codeine, H2-histamine receptor blockers, and propranolol (slows down inactivation). Myelotoxic drugs enhance the manifestations of the hematotoxicity of the drug.

Storage Conditions

In a light-protected place at a temperature not lower than +5°C (41°F). Do not allow freezing. Keep out of reach of children.

Shelf Life

Shelf life. 3 years. Do not use after the expiration date printed on the package.

Dispensing Status

The drug is dispensed by prescription.

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.