How Do Ophthalmic Anesthetics Work?

Ophthalmic antibiotics combos are combination formulations of two or more antibiotics. Ophthalmic antibiotics are ointments or solutions that are used to treat and prevent bacterial infections in the eyes. Each antibiotic works in a different way to kill bacteria and/or prevent its growth, hence, antibiotic combos can simultaneously target different processes involved in bacterial growth.

Ophthalmic antibiotic combos work in the following ways to kill bacteria and inhibit its growth:

• Create fissures in the bacterial cell membrane, causing cell contents to leak out and enabling the absorption of antibiotics into the bacterial cell.
• Prevent the bacteria from using amino acids and enzymes to synthesize the proteins required for their survival.
• Prevent the growth of bacterial cell walls, the layer over the bacterial cell membrane, which protects them when they grow and helps maintain their shape.

Ophthalmic antibiotics combos are effective against both gram-positive and gram-negative bacteria, and are useful in treating multi-drug resistant bacterial infections. Gram-positive and gram-negative bacteria are structurally different and are classified depending on whether they get stained or not by a violet dye used in laboratory tests known as the Gram stain test.

Ophthalmic antibiotic combos are used to treat ocular infections caused by bacteria such as Staphylococci, Streptococci, Haemophilus influenzae and Pseudomonas aeruginosa. Eye conditions treated with antibiotic combos include:

• Bacterial conjunctivitis (infection of the conjunctiva which includes the whites of the eyes and the inner surface of eyelids)
• Blepharitis (infection in the eyelid margins)
• Blepharoconjunctivitis (inflammation of the eyelid margin and the surrounding conjunctiva)
• Infection or inflammation in the cornea or the eyeball
• Prophylaxis to prevent infection after eye surgeries

Side effects include:

• Eye irritation and redness
• Eye pain, stinging and/or burning
• Hypersensitivity reactions such as
  • Eye itching
  • Rash around the eyes
  • Swelling of eyelids and other surrounding areas
  • Allergic contact dermatitis
• Conjunctival edema
• Conjunctival redness

The information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with your doctor or pharmacist to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking your medication and never change your dose or frequency without consulting your doctor.

Drug names include:

• Polymyxin B/bacitracin ophthalmic
• Neomycin/polymyxin B/gramicidin ophthalmic
• Neomycin/polymyxin B/bacitracin ophthalmic (Lumi-Sporyn)
• Trimethoprim/polymyxin B ophthalmic (Polytrim Ophthalmic solution)