<p>Serious, life threatening, hypersensitivity (anaphylactic) reactions have been reported in some cats following application of antibiotic ophthalmic preparations. If your cat has swelling of the face, itching, appears weak, vomits, or has difficulty breathing within 4 hours of application you should discontinue treatment and contact your veterinarian immediately. The use of oxytetracycline and other antibiotics may result in an overgrowth of resistant organisms such as Monilia, staphylococci, and other species of bacteria. If new infections due to nonsensitive bacteria or fungi appear during therapy, appropriate measures should be taken.</p>