Polymyxin-B for Injection (polymyxin B sulphate) is used for the treatment of patients with Urinary tract infections caused by Pseudomonas aeruginosa and Escherichia coli, Bloodstream infections caused by Pseudomonas aeruginosa, Enterobacter (formerly called Aerobacter) aerogenes and Klebsiella pneumonia, Meningeal infections caused by Pseudomonas aeruginosa, and Corneal and subconjunctival eye infections caused by Pseudomonas aeruginosa.
Polymyxin B for Injection will be administered by a health specialist in a hospital or under direct supervision and monitoring by a healthcare professional. Although it is common to feel better early in the course of therapy, the medicine should be used exactly as directed.
Polymyxin-B Injection may be administered intravenously, intramuscularly or intrathecally only to hospitalized patients under constant supervision. Do not exceed the dosage 2.5 mg/kg/day or 200 mg/day. Larger doses may be responsible for nephrotoxicity. Transient neurotoxic signs/symptoms may be noted with therapeutic doses.
Adults and Children (Older than 2 years): A total of 1.5 to 2.5 mg/kg/day in patients with normal kidney function. Do not exceed the total daily dose 2.5 mg/kg/day or in any case, 200 mg/day.
Elderly (≥ 65 years): The renal status of elderly patients may be impaired, therefore the renal function assessment is required prior to and regularly during treatment to provide guidance for dosing in such patients.
Patients with Renal Impairment: Polymyxin-B sulphate is eliminated primarily by the kidney and therefore reduce the dosage from 1.5 mg/kg for patients with kidney impairment. There are no available dosing recommendations for patients on peritoneal dialysis- or hemodialysis. Infusions may be given every 12 or 8 hours over a period of around 60-90 minutes.
Adults and Children (Older than 2 years): The dosage is 1.5 to 2.5 mg/kg/day in patients with normal kidney function. Dosage can be divided and given at either 4-6 hour intervals.
Elderly (≥ 65 years): The renal status of elderly patients may be impaired, therefore assess renal function prior to and on a regular basis during treatment.
Patients with Renal Impairment: Reduce the dosage in patients with kidney impairment. There are no dosing recommendations available for patients on peritoneal dialysis or hemodialysis. Do not consider intramuscular administration routinely because of the severe pain at injection sites, mainly in children. Pain may be immediate or delayed.
Adults and Children (Older than 2 years): Dosage is 5 mg once a day intrathecally for 3 or 4 days, then 5 mg once every other day for at least 14 days after cultures of the cerebrospinal fluid are negative and sugar content has returned to normal.
Infants (less than 2 years): Dosage is 2 mg once a day intrathecally for 3-4 days or 2.5 mg once every other day. Continue with a dose of 2.5 mg once every other day for at least 14 days after cultures of the cerebrospinal fluid are negative and sugar content has returned to normal.
The most commonly reported side effects due to Polymyxin B for Injection may include:
- cellular casts
- diminishing urine output and rising BUN
- blurred vision
- facial flushing
- slurring of speech
- pain at the injection site
- skin redness and itching
Warnings and Precautions:
- Polymyxin-B injection need to be used where sensitivity suggests more commonly used systemic antibacterial agents may be contraindicated or ineffective due to bacterial resistance.
- Polymyxin Injection, if prescribed for intravenous, intramuscular or intrathecal administration, needs to used only in hospitalized patients under precise monitoring for kidney function as well as neurological signs/symptoms.
- In order to reduce the development of drug-resistant bacteria and maintain the impact of polymyxin-B sulfate and other antibacterial drugs, polymyxin-B should be considered only to treat/prevent infections that are proven or strongly suspected to be caused by the susceptible bacteria.
- Patients who are known to hypersensitive to polymyxins, including polymyxin B sulfate, or to any component of the container should not use this medicine. This injection is contraindicated in patients with myasthenia gravis.
- Injection Polymyxin-B is nephrotoxic therefore assess renal function prior to and on a regular basis during treatment. Dose adjustment is needed in patients with reduced renal function.
- Polymyxin-B 500000 IU Injection at therapeutic doses may cause severe neurotoxic symptoms as manifested by seizure, ataxia and neuromuscular blockade. These are typically associated with high drug serum levels observed in patients with impaired renal function or nephrotoxicity.
- The concurrent/sequential administration of anaesthetic and other neurotoxic medicines needs to be avoided with Polykris treatment. The neurotoxicity of this drug can result in respiratory paralysis from neuromuscular blockade, mainly when the medicine is given soon after muscle relaxants and/or anaesthesia. In case signs of respiratory paralysis occurs, assist respiration and withdraw the medicine.
- Injection Polymyxin B sulphate is not active and therefore do not use to treat bacterial infections caused by gram-negative bacteria (Proteus spp., Morganella spp., Providencia spp., Serratia marcescens, Neisseria spp., Burkholderia spp.), all gram-positive bacteria and anaerobes.
- The intramuscular, intravenous, or intrathecal administration of Polymyxin injection should be restricted to hospitalized patients so as to provide constant clinical supervision. Do not exceed the maximum dosage 2.5 mg/kg/day or a total of 200 mg/day in patients with normal renal function.
- The intramuscular dosage is not recommended routinely due to severe pain at injection sites. When procaine is used with Polykris injection to lessen the pain of intramuscular injection, care needs to be taken not to give; intrathecally or intravenously, solutions that have been prepared with procaine for intramuscular administration.