POLY-B Injection

Uses
Poly-B (Polymyxin B sulfate) is an injectable antibiotic indicated in the treatment of infections of the urinary tract, meninges, and bloodstream that are the result of susceptible strains of Ps. aeruginosa. Eye infections caused by susceptible strains of Ps. aeruginosa can also be treated by Poly-B.

Dosage and Administration
Poly-B come in a vial containing 500,000 units of Polymyxin B Sulphate.

Polymyxin B Sulphate can be administered by injection in to a muscle or a vein. In cases of eye infection it can be applied topically.

To administer Intravenously: One vial should be dissolved in 300 to 500 mL of solution for parenteral dextrose injection 5% for continuous drip. A dosage of 15,000 to 25,000 units/kg body weight/day is usually given to adults with no kidney problems. A lower dosage should be given to adults with kidney impairment or to children or infants.

To Administer Intramuscularly: Dissolve one Poly-B vial in 2 mL sterile water for injection or sodium chloride injection or procaine hydrochloride injection 1%. A dosage of 25,000 to 30,000 units/kg/day should be given to healthy adults. Children and patients with renal problems require a lower dosage.

To Administer Intrathecally: Dissolve one vial of Poly-B in 10 mL sodium chloride injection USP. A dosage of 50,000 units once daily is given for 3 to 4 days. This is then reduced to 50,000 units once every second day for at least 2 weeks after cultures of the cerebrospinal fluid are negative and sugar content has returned to normal.

To Administer Opthalmically: Dissolve one Poly-B vial in 20 to 50 mL sterile water for injection or sodium chloride injection USP. Drops should be applied 1 to 3 times per hour.

Side effects
The most serious side effect resulting from use of Polymyxin B Sulphate is called Clostridium difficile associated diarrhea (CDAD) or sometimes called Antibiotic-Associated Diarrhea (AAD). This is a diarrhea caused by changes in the composition and function of the intestinal flora. It can result mild to sever diarrhea and in some cases can cause fatal colitis. If you experience diarrhea while taking Poly-B injection, contact your doctor.

Other side effects associated with Polymyxin B Sulphate include

• albuminuria
• cylinduria
• azotemia
• facial flushing
• dizziness progressing to ataxia
• drowsiness
• peripheral paresthesias
• fever
• headache
• stiff neck
• urticarial rash
• severe pain at intramuscular injection sites
• thrombophlebitis at intravenous injection sites

Precautions
Renal function must be determined prior to use. Patients with renal issues will require dosage adjustments.

Only give Poly-B intramuscularly or intrathecally to hospitalized patients under medical supervision.

If you are taking any neurotoxic or nephrotoxic drugs (including bacitracic, neomycin, streptimycin, kanamycin, tobramycin, gentamycin, amikacin, cephaloridine, paromomycin, colistin and viomycin) these should not be taken with Polymyxin B Sulphate.