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Polymyxin B and trimethoprim eye drops

Brand names: Polytrim

Polytrim eye drops treat bacterial pink eye.

Brand namesPolytrim
Type of medicineAntibiotic eye drops
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

Most pink eye is viral and doesn't need antibiotics.

What it's used for

  • Bacterial pink eye (conjunctivitis)

How to take it

  • Wash your hands, tilt your head back, and put a drop in the pocket of the lower lid without touching the tip to your eye.
  • Wait 5 minutes between different eye drops.
  • Use as directed, usually every 3 hours while awake for 7 to 10 days.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Burning or stinging
  • Redness
Call 911Swelling of the face, lips, or throat, hives, or trouble breathing
Call your provider todayEye pain, light sensitivity, or blurry vision (needs same-day eye care)

Warnings

  • Contact lens wearers with a red, painful eye need an eye exam the same day.

Other medicines, foods, and alcohol

  • Few interactions.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Ask your provider.

Missed doses, overdose, and storage

If you miss a dose

Apply it when you remember, then go back to your usual schedule. Don't apply extra to make up for it.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.