Polymyxin B is used to treat serious bacterial infections. These include Pseudomonas aeruginosa infections in the urinary tract, meninges, or in the blood.


What is Polymyxin B?

Polymyxin B interacts with some component of the outer membrane of Gram negative bacteria. In this way, it penetrates through the membrane and kills sensitive bacteria.  


How should Polymyxin B be taken?

Polymyxin B can be administered intramuscularly or intravenously via infusion. This medication also exists in ophthalmic and topical forms.


Side effects associated with Polymyxin B

Prolonged or repetitive use of polymyxin b may cause a second infection.


Among the other possible side effects of polymyxin B include the following:


  • Fever
  • Pain at the injection site


It is important to contact a doctor immediately if you experience:


  • Rash
  • Urticaria
  • Itch
  • Difficulty breathing
  • Tightness in the chest
  • Swelling of the mouth, face, lips or tongue
  • Changes in urination frequency
  • Hard of hearing or tinnitus
  • Dizziness
  • Drowsiness
  • Redness in the face
  • Loss of coordination
  • Changes in mood or behavior
  • Severe headaches
  • Stiff neck
  • Swelling and redness at the injection site
  • Tingling or numbness in the mouth, hands or feet
  • Unusual weakness
  • Rapid heartbeat
  • Vision problems


Contraindications and warnings associated with the use of Polymyxin B

Before starting treatment with polymyxin B, it is important to tell your doctor if:


  • You have any allergies to the active substance, its excipients, or to any other drugs, food and various substances  
  • You are taking any other medications, herbal remedies or supplements. Mentioning in particular: aminoglycosides, muscle relaxants or drugs that can cause damage to the kidneys
  • You are suffering (or have suffered) from kidney problems or neuromuscular disorders
  • You are pregnant or breast-feeding


Treatment with polymyxin B can compromise the ability to drive or operate hazardous machinery. This side effect can be aggravated by alcohol and certain other medications.