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Polymyxin b Side Effects

Medically reviewed by Last updated on Feb 22, 2021.

For the Consumer

Applies to polymyxin b: injection powder for solution

Side effects requiring immediate medical attention

Along with its needed effects, polymyxin b may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking polymyxin b:

Incidence not known

  • Dizziness
  • drowsiness
  • fever
  • headache
  • numbness or tingling in hands or feet
  • pain in the lower back or side
  • shakiness and unsteady walk
  • stiff neck
  • unsteadiness, trembling, or other problems with muscle control or coordination

Side effects not requiring immediate medical attention

Some side effects of polymyxin b may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known

  • Changes in skin color, pain, tenderness, or swelling at the injection site
  • face is warm or hot to touch
  • hives or welts
  • itching
  • redness of the skin
  • skin rash

For Healthcare Professionals

Applies to polymyxin b: compounding powder, injectable powder for injection


Frequency not reported: Nephrotoxic reactions (including albuminuria, cylindruria, azotemia)[Ref]


Frequency not reported: Rising blood levels with no increase in dose, drug fever[Ref]

Nervous system

Frequency not reported: Neurotoxic reactions (including facial flushing, dizziness progressing to ataxia, drowsiness, peripheral paresthesias [circumoral, feet, hands), signs of meningeal irritation with intrathecal administration [e.g., fever, headache, stiff neck, increased cerebrospinal fluid cell count, increased cerebrospinal fluid protein])[Ref]


Apnea due to coadministration with curariform muscle relaxants, other neurotoxic agents, or inadvertent overdosage has been reported.[Ref]

Frequency not reported: Apnea[Ref]


Frequency not reported: Urticarial rash[Ref]


Frequency not reported: IM injection site pain, IV injection site thrombophlebitis[Ref]

Frequently asked questions


1. "Product Information. Polymyxin B Sulfate (polymyxin B sulfate)." AuroMedics Pharma LLC, Dayton, NJ.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.