Subvixin (Powder) Instructions for Use

ATC Code

J01XB02 (Polymyxin B)

Active Substance

Polymyxin B

Polymyxin B (Rec.INN registered by WHO)

Clinical-Pharmacological Group

Antibiotic of the polypeptide group

Pharmacotherapeutic Group

Systemic antibacterial agents; other antibacterial agents; polymyxins

Pharmacological Action

An antibiotic of polypeptide structure. The mechanism of action is primarily due to the blockade of the permeability of the cytoplasmic membrane of bacterial cells, leading to their destruction.

It is active against most gram-negative bacteria: Escherichia coli, Enterobacter spp., Klebsiella spp., Haemophilus influenzae, Bordetella pertussis, Salmonella spp., Shigella spp.; it is especially active against Pseudomonas aeruginosa.

Vibrio cholerae (except for Vibrio cholerae eltor) and Coccidioides immitis are also sensitive to polymyxin B, but most fungi show resistance to this antibiotic.

Serratia marcescens, Providencia spp., Bacteroides fragilis are usually resistant. It is not active against Proteus spp., Neisseria spp., obligate anaerobic and gram-positive bacteria.

It exhibits cross-resistance with colistin.

Pharmacokinetics

After intramuscular administration, the C_max in plasma is reached within 2 hours. Plasma protein binding is 50%.

It penetrates poorly through tissue barriers and does not cross the blood-brain barrier. It crosses the placenta in small amounts and is excreted in breast milk. It is not metabolized.

It is excreted by the kidneys unchanged (60% within 3-4 days) and through the intestines. The T_1/2 is 3-4 hours; in severe renal failure, it is 2-3 days. It does not accumulate upon repeated administration.

Indications

Severe infectious and inflammatory diseases caused by gram-negative microorganisms sensitive to polymyxin B with multiple resistance to other antibiotics: sepsis, meningitis, pneumonia, skin and soft tissue infections, including wound infections, infections in burn patients.

ICD codes

Dosage Regimen

Administer the reconstituted powder intravenously, intramuscularly, or intrathecally. Determine the specific route, dose, and duration individually based on the infection’s severity, causative pathogen susceptibility, and patient’s clinical status.

For intravenous infusion, dissolve the powder in Sterile Water for Injection. Further dilute the resulting solution in 300-500 mL of 5% Dextrose Injection. Infuse slowly over 60-90 minutes.

For intramuscular injection, dissolve the powder in Sterile Water for Injection or 1% Procaine Hydrochloride Solution. Administer the injection deep intramuscularly. Divide the total daily dose into 2-4 equal injections given at regular intervals.

For intrathecal administration in cases of meningitis, dissolve the powder in Sodium Chloride Injection without a preservative. Use this route only when the meninges are infected.

The typical adult and pediatric daily dose is 15,000-25,000 units/kg/day. Do not exceed a total daily dose of 2,000,000 units (200 mg). In life-threatening infections, a higher initial dose may be used under strict medical supervision.

For adults, the usual daily intramuscular or intravenous dose is 1,000,000-1,500,000 units. For intrathecal administration in adults, administer 50,000 units once daily for 3-4 days, then 50,000 units every other day until cerebrospinal fluid cultures are negative.

For pediatric patients, the daily dose is also 15,000-25,000 units/kg/day. For intrathecal administration in children over 2 years of age, use the same dose as for adults. For infants under 2 years, the intrathecal dose is 20,000 units once daily for 3-4 days or 25,000 units every other day.

Adjust the dosage regimen in patients with pre-existing renal impairment. Monitor renal function before and during therapy. Reduce the dose or increase the dosing interval if necessary based on creatinine clearance.

The usual duration of therapy is 7-14 days. Continue treatment for at least 3 days after fever subsides and clinical symptoms resolve.

Adverse Reactions

Nervous system disorders: dizziness, ataxia, impaired consciousness, drowsiness, paresthesia, neuromuscular blockade.

Urinary system disorders: albuminuria, cylindruria, azotemia, proteinuria, renal tubular necrosis.

Respiratory system disorders: paralysis of respiratory muscles, apnea.

Digestive system disorders: epigastric pain, nausea, decreased appetite, pseudomembranous colitis.

Allergic reactions: skin rash, itching, eosinophilia.

Local reactions: phlebitis, periphlebitis, thrombophlebitis, pain at the intramuscular injection site.

Other: visual disturbances, superinfection, candidiasis; with intrathecal administration – meningeal symptoms.

Contraindications

Hypersensitivity to polymyxin B; myasthenia gravis.

With caution in chronic renal failure.

Use in Pregnancy and Lactation

Contraindicated for use during pregnancy.

If use during lactation is necessary, the issue of discontinuing breastfeeding should be considered.

Use in Renal Impairment

Polymyxin B should be used with caution in chronic renal failure.

Pediatric Use

It can be used in children according to indications, in age-appropriate recommended doses and regimens. It is necessary to strictly follow the instructions in the polymyxin B drug labels regarding the dosing regimen for children of different ages.

Special Precautions

For infections caused by gram-negative microorganisms (Enterobacter, Pseudomonas aeruginosa, etc.), polymyxin B is prescribed only when the pathogen is resistant to other less toxic antimicrobial drugs.

It is used parenterally only in a hospital setting.

During parenteral use, monitoring of the plasma concentration of polymyxin B is necessary.

During long-term treatment, renal function should be monitored every 2 days.

Polymyxin B can be used as part of combination drugs with neomycin, bacitracin, nystatin, trimethoprim, as well as with dexamethasone.

Drug Interactions

Polymyxin B is incompatible with non-depolarizing muscle relaxants (risk of respiratory muscle paralysis).

When used concomitantly, a synergistic effect is observed with chloramphenicol, carbenicillin, tetracycline, sulfonamides, and trimethoprim against Pseudomonas aeruginosa, Proteus spp., Serratia spp.; with ampicillin – against most gram-negative bacteria.

It is compatible with bacitracin and nystatin.

When combined with aminoglycosides (kanamycin, streptomycin, neomycin, gentamicin), the risk of oto- and nephrotoxicity, as well as neuromuscular blockade, increases.

It increases the nephrotoxicity of amphotericin B.

Pharmaceutical incompatibility with the sodium salt of ampicillin, chloramphenicol, cephalosporin antibiotics, tetracycline, amino acid solutions, heparin; they should not be mixed in the same syringe or infusion medium.

Storage Conditions

Store at 2°C (36°F) to 25°C (77°F). Keep in original packaging, protected from light. Keep out of reach of children.

Dispensing Status

Rx Only

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.