FURAZIDIN

INSTRUCTIONS FOR MEDICAL USE OF THE MEDICINAL PRODUCT FURAGIN (FURAGIN)

Composition:

Active substance: 1 tablet contains 50 mg of furazidin, calculated as 00% substance;
Excipients: Lactose monohydrate and microcrystalline cellulose mixture (3:1) – Cel lac tose-80, potato starch, magnesium stearate, polysorbate-80.

Pharmaceutical form. Tablets.

Main physicochemical properties: round-shaped tablets with a biconvex surface, yellow to yellow with an orange tint, with slightly uneven surface coloration; presence of specks of more intense color is acceptable.

Pharmacotherapeutic group. Antimicrobial agents for systemic use. Nitrofuran derivatives. Furazidin. ATC code J01X E03.

Pharmacological properties.

Pharmacodynamics.

Furagin is a nitrofuran antibacterial agent with bacteriostatic activity. It is effective against gram-positive (Staphylococcus epidermidis, Staphylococcus aureus, Staphylococcus faecalis) and gram-negative (Enterobacteriaceae, Klebsiella spp., Escherichia coli) bacteria. The high bacteriostatic activity of furazidin is associated with the presence of an aromatic nitro group. Resistance to furazidin develops slowly. Furazidin inhibits microbial enzyme systems as well as other biochemical processes within the bacterial cell, thereby disrupting the cytoplasmic membrane and the bacterial cell wall.

Pharmacokinetics.

Absorption. Furazidin is well absorbed from the gastrointestinal tract. Absorption of the drug occurs mainly from the distal portion of the small intestine via passive diffusion (absorption is several times higher than from the proximal portion). After a single 200 mg dose, the maximum concentration of furazidin in blood plasma is reached within 30 minutes, remains at this level for 1 hour, and then gradually decreases. Bacteriostatic concentrations of furazidin in blood plasma are maintained for 8–12 hours. Furazidin binds to plasma proteins.

Metabolism/Elimination. Approximately 10% of the administered dose is metabolized in the liver and kidneys. In case of impaired renal function, a larger portion of the administered dose undergoes biotransformation. The elimination half-life of furazidin is short (approximately 1 hour). Furazidin is excreted primarily by the kidneys via tubular secretion (85%). 8–13% of furazidin is excreted unchanged in urine, where its concentration is, on average, many times higher than the minimum inhibitory concentration for most susceptible bacteria. The maximum concentration of furazidin in urine is 5.7 µg/mL.

Furazidin readily crosses the placental barrier.

Clinical characteristics.

Indications.

Acute and chronic urinary tract infections: pyelonephritis, cystitis, urethritis, prostatitis, postoperative infections of the urogenital system.

Contraindications.

• Hypersensitivity to furagin, nitrofuran derivatives, or to any excipients of the medicinal product.
• Severe renal impairment (creatinine clearance less than 30 mL/min).

− Severe hepatic impairment.

• Polyneuropathy (including diabetic polyneuropathy).
• Glucose-6-phosphate dehydrogenase deficiency (risk of hemolysis).
• Porphyria (disorders caused by impaired metabolism of hemoglobin breakdown products).
• Rare congenital galactose intolerance, lactase deficiency, or glucose-galactose malabsorption.
• Deficiency of sucrase/isomaltase/lactase, lactose intolerance.

Contraindicated in patients undergoing hemodialysis or peritoneal dialysis.

Contraindicated in children (under 18 years of age).

Not to be used during pregnancy and breastfeeding.

Furagin is not recommended for urosepsis and parenchymal kidney infection.

Interaction with other medicinal products and other forms of interaction.

Medicinal products that alkalinize urine reduce the therapeutic effect of Furagin (they accelerate the excretion of furazidin in urine).

Agents that acidify urine (acids, including ascorbic acid, as well as calcium chloride) increase the concentration of furazidin in urine (slowing its excretion), thereby enhancing the therapeutic effect of the drug, but simultaneously increasing the risk of increased toxicity.

Concomitant use with chloramphenicol, ristomycin, and sulfonamides enhances suppression of hematopoiesis.

Due to antagonism of action between Furagin and quinolones (nalidixic acid, oxolinic acid, norfloxacin), simultaneous use of these drugs should be avoided.

Concomitant use of probenecid and sulfinpyrazone reduces the excretion of furazidin, increasing the risk of adverse reactions and toxicity.

Simultaneous use of Furagin and antacids (containing magnesium trisilicate) reduces the absorption of furazidin.

In renal impairment, concomitant use of Furagin with aminoglycosides is not recommended. The antibacterial effect of Furagin is significantly enhanced when used concomitantly with antibiotics (penicillins and cephalosporins), and it combines well with tetracycline and erythromycin.

Alcohol must not be consumed during treatment, as alcohol may intensify the severity of adverse effects (palpitations, chest pain, headache, nausea, vomiting, seizures, hypotension, fever, anxiety).

Special precautions for use.

The drug should be used with caution in the following cases:

• anemia;
• deficiency of B-group vitamins and folic acid;
• lung diseases;

Peripheral neuropathy (pain, sensory disturbances in the area innervated by the affected nerve) may develop during prolonged use of Furagin. If symptoms of neuropathy occur, the drug should be discontinued;

Furagin may cause polyneuropathy in patients with diabetes mellitus.

The use of Furagin is not recommended in cases of urosepsis and parenchymal kidney infection.

Experimental studies and clinical observations in patients have shown that nitrofurans adversely affect testicular function, manifested by a decrease in sperm and ejaculate volume, reduced sperm motility, and pathological changes in sperm morphology.

Diarrhea may occur during Furagin treatment as a result of suppression of normal colonic microflora.

In rare cases, pseudomembranous colitis may develop, caused by suppression of the natural rectal microflora and overgrowth of Clostridium difficile. In mild cases of pseudomembranous colitis, discontinuation of the drug is sufficient. During appropriate therapy, avoid using drugs that slow intestinal peristalsis. Taking Furagin with food reduces the risk of colitis without significantly affecting drug absorption.

Laboratory testing in patients taking Furagin may yield false-positive results for glucose in urine when the copper reduction method is used. Furagin does not affect glucose detection in urine by enzymatic methods.

During prolonged therapy, regular blood tests (leukocyte count), monitoring of liver and kidney function, and assessment of lung function should be performed, especially in patients aged 65 years and older.

To prevent neuritis, concomitant use of antihistamines and B-group vitamins (nicotinamide, thiamine) is advisable.

If you have known intolerance to certain sugars, consult your doctor before taking this medicinal product.

Use during pregnancy or breastfeeding.

Use during pregnancy or breastfeeding is contraindicated.

Ability to affect reaction speed when driving or operating machinery.

The drug usually does not affect reaction speed when driving or operating machinery. However, individuals who experience dizziness, drowsiness, or other central nervous system side effects during treatment should exercise caution.

Method of Administration and Dosage

The drug should be taken orally, immediately after a meal, with a large amount of water.

Adults: 100–200 mg (2–4 tablets) 2–3 times daily. The treatment course lasts 7–10 days, depending on the severity of the disease, treatment efficacy, and renal function. If necessary, the treatment course may be repeated after 10–15 days.

Maximum daily dose: 600 mg.

If a dose is missed, the next dose should be taken as soon as the patient remembers. A double dose should not be taken to make up for the missed dose.

Children. The drug is not intended for use in children.

Overdose.

Toxic effects usually occur in patients with impaired kidney function.

Symptoms: headache, dizziness, depression, peripheral polyneuritis, allergic reactions (urticaria, angioneurotic edema, bronchospasms), nausea, vomiting, hemolytic anemia (in patients with glucose-6-phosphate dehydrogenase deficiency), megaloblastic anemia, and rarely, liver function disorders.

Treatment: discontinue the drug, ensure high fluid intake, use enterosorbents, antihistamines, and B-group vitamins (thiamine bromide). Symptomatic therapy. In severe cases – hemodialysis. There is no specific antidote.

Side effects

Furagin, like other medicinal products, may cause adverse reactions, which do not occur in all patients.

Classification of adverse reaction frequencies: very common (≥ 1/10); common (≥ 1/100 to <1/10); uncommon (≥ 1/1000 to <1/100); rare (≥ 1/10,000 to <1/1000); very rare (<1/10,000), including isolated cases; unknown (cannot be estimated from available data).

Blood and lymphatic system disorders: very rare – blood dyscrasias (agranulocytosis, thrombocytopenia, aplastic anemia).

Immune system disorders: hypersensitivity reactions, including itching, rash, urticaria, angioedema.

Nervous system disorders: uncommon – dizziness, drowsiness; rare – peripheral neuropathy.

Eye disorders: rare – visual disturbances.

Respiratory, thoracic and mediastinal disorders: rare – acute and chronic pulmonary reactions.

Acute pulmonary reaction develops rapidly and is characterized by severe dyspnea, fever, chest pain, cough with or without sputum, and eosinophilia (increased number of eosinophilic granulocytes in blood). Skin rash, pruritus, urticaria, myalgia (muscle pain), and angioedema (facial, neck, oral cavity and laryngeal tissue swelling) have been reported concurrently with acute pulmonary reaction. Acute pulmonary reaction is based on hypersensitivity reaction, which may develop within several hours, rarely within minutes. Acute pulmonary reaction resolves upon discontinuation of the drug. Chronic pulmonary reaction may develop after a prolonged period following cessation of nitrofuran therapy (including nitrofurantoin). Typical features include progressive dyspnea, tachypnea, unstable fever, eosinophilia, progressive cough, and interstitial pneumonia and/or pulmonary fibrosis.

Gastrointestinal disorders: uncommon – decreased appetite, nausea; rare – vomiting, diarrhea; very rare – pancreatitis.

Skin and subcutaneous tissue disorders: rare – papular rash, pruritus; very rare – angioedema, urticaria, exfoliative dermatitis, erythema multiforme.

Musculoskeletal and connective tissue disorders: very rare – arthralgia (joint pain).

General disorders: rare – weakness, increased body temperature, temporary hair loss.

Hepatobiliary disorders: very rare – cholestatic jaundice, hepatitis.

Furagin may discolor urine to dark yellow or brown.

To reduce adverse effects, it is recommended to take vitamin B complex, antihistamines, and drink plenty of fluids. In case of pronounced adverse reactions, the dose should be reduced or the drug discontinued.

If adverse reactions occur during treatment that are not listed in the instructions for medical use, a physician must be informed.

Shelf life. 2 years.

Storage conditions.

In original packaging at temperature not exceeding 25 °C. Keep out of reach of children.

Packaging. Tablets, 10 in a blister, 3 blisters in a carton.

Prescription category. Prescription only.

Manufacturer.

JSC "Kyivmedpreparat" or JSC "Halychpharm".

Manufacturer's address.

139 Saksaganskogo Street, Kyiv, 01032, Ukraine

or 6/8 Opryshkovska Street, Lviv, 79024, Ukraine.