After their (hopefully) successful treatment, patients may tell you about being treated with medications with names ending in ‘floxacin’. These are classed as quinolones and are licensed for the more common classes of bacterial keratitis and severe conjunctivitis. Other medications generally reserved for cases where Pseudomonas aeruginosa is suspected fall within a group called aminoglycosides. These may be gentamicin or tobramycin eye drops/ointment.
This aggressive bacterium can have devastating effects and should always be thought of as at least a possibility in cases of a soft contact lens wearer with an eye infection. You might wonder why bactericidal medications that kill bacteria are not used more frequently than bacteriostatic medications, which seem less powerful. The answer lies in the ongoing challenge of bacterial resistance, whereby a minute fraction of bacterium that encounters a drug for the first time is resistant to it, then passes on this resistance to their next generation.
The more powerful antibiotics are used less frequently, so that they may be more effective when really needed. It is important that patients complete their course of therapy as prescribed, only changing their treatment on the advice of the original prescriber. If possible read the patient information leaflet in cartons of medication but do not break the carton seal. We must assume at least some of the medication will be absorbed systemically by the body, and some medications specifically caution against use in pregnancy or while breastfeeding. Good sources of information are the British National Formulary, the Monthly Index of Medical Specialities, and Net Doctor.