Penicillin in ophthalmology

Abstract

1. Dosage.-In the strength used by us (drops, 500 units per c.cm.; ointment, 100 units per gramme) penicillin would appear to retain its potency for 4 hours (drops) and 6 hours (ointment). Frequency of treatment can thus be regulated according to the requirements of the case: very frequent applications of penicillin would seem unnecessary. 2. Iindications for Use.-All observers are agreed that penicillin affords the best results in blepharitis; most of us would add acute conjunctivitis, but I have already indicated the small number of cases of acute infective conjunctivitis that occur under Service conditions- at least, in my experience. I do believe that in civilian practice, particularly in the hospital out-patient departments, penicillin will be the treatment of choice in these cases. The same remarks apply to corneal ulcers (infective). In chronic dacryocystitis I believe also it will become habitual to use penicillin preliminary to operation, but the cases seen have been too few for further comment. Recurrent styes and infected chalazion seem to be limited by applying penicillin, particularly in the intervals between recurrences. As certain indications for penicillin I would add to the above (I) all cases of serious injury to the eye, whether penetrating or not; (2) all cases of facial burns involving the eye; (3) routine postoperative treatment. It is impossible to assess the value of the drug in cases of injury, because there is no control for comparison. I have not yet had sufficient cases of penetrating injury to conclude whether the incidence of sepsis is less than before penicillin was employed. This is a matter requiring further investigation. Nor have I any evidence that non-infected cases heal more quickly with penicillin. Nevertheless I would advocate its use. There remain a large assortment of cases in which penicillin has been used with doubtful or conflicting results. Chronic conjunctivitis seems to respond slightly, and the consensus of opinion is, I think, that penicillin is not of much value. Here I would repeat what I have mentioned above-that where a secondary infection with a penicillin-sensitive organism is also present, by inhibiting the growth of such an organism the drug may indirectly aid and accelerate healing. This statement applies to many inflammations which are, per se, unaffected by penicillin-such as episcleritis, trachoma, phlyctenular keratitis, marginal ulceration, herpetic keratitis, and many others. Two observers in this series have been struck by the benefit obtained with penicillin in cases of infected socket. I have been impressed, in a series of 6 cases (seen outside the date range of the report), by the inefficacy of the drug. I found after some experimentation that 24% red prontosil was much more effective. There are therefore some types of ocular inflammation which require much more extensive investigation before we can be sure how much to expect from the use of penicillin. With regard to recurrence of inflammation I can say little yet. Because cases of one's own have not returned does not mean that there have been no recurrences; the patients may have gone to another part of the country. My opinion is that penicillin, being bacteriostatic and not bactericidal, will have little power to prevent recurrences unless it can be used, more or less as a routine, in intervals between exacerbations. Finally, it must be remembered that many ocular inflammations are secondary to, or at least run parallel with, other affectionse. g., blepharitis and seborrhoeic dermatitis, conjunctivitis and rosacea, etc. The treatment of the underlying condition must not be lost sight of in the enthusiasm of employing a new method. I believe penicillin to be quite useless in cases of deep keratitis, iritis, or cyclitis. In conclusion I should like to emphasize the desirability of those concerned ensuring that all cases of facial burns with ocular involvement be given penicillin from the very beginning of treatment. In such a way I believe a number of ulcers from exposure keratitis can be avoided. © 1944, British Medical Journal Publishing Group. All rights reserved.