As far as we know, the treatment of conditions indicative of maxillary sinusitis with chloramphenicol eye drops has not previously been described. In this pilot study, in which peroral antibiotics were compared to chloramphenicol eye drops, 14 of 18 patients in the chloramphenicol group (78 %) answered that they noticed clear improvement after three days of treatment, while the corresponding number in the group treated with peroral antibiotics was five of 15 (33 %). On average, patients in the chloramphenicol group reported improvement 1.3 days sooner than patients in the tablet group.
Ideally, this study should have compared treatment with chloramphenicol eye drops to placebo. However, patients who see their GP because they suffer from symptoms indicative of sinusitis expect to receive «effective» treatment that works fast. Consequently, no placebo group was formed, nor a group for no treatment.
Our study did not collect information about which types of peroral antibiotics the GPs chose to prescribe. It is a matter for discussion whether a standardised choice of antibiotics might have contributed to a more homogenous basis for comparison between the two groups. On the other hand, our design ensured that the treatment was as similar as possible to the treatment the GPs would have chosen in normal practice.
The trial’s total follow-up period was ten days from commencement of treatment. This was primarily a pilot study looking at effectiveness, side effect frequency and patient satisfaction, and was thus not specifically designed to look into the presence of residual symptoms after treatment had been completed. Later trials should include this matter as part of their remit.
A more recent literature review concludes that antibiotics have limited effect and that their use should be limited in the treatment of clinically diagnosed acute sinusitis (15). For this reason, it may now be better to compare treatment with chloramphenicol eye drops to saline drops applied in the conjunctiva or no medicinal treatment. However, studies suggest that saline nasal spray scores no better than placebo in the treatment of conditions indicative of acute sinusitis (16).
If our results can be confirmed by studies conducted on a larger scale, treatment with chloramphenicol eye drops may become an option in cases of acute maxillary sinusitis. The benefits may be a shorter treatment period and fewer side effects. Nevertheless, this treatment will never represent an option for everyone suffering from this type of condition. For many, a saline rinse or no treatment will still be a possibility, while treatment with systemic antibiotics should be reserved for febrile patients whose general state of health has been reduced by sinusitis, and for patients who are allergic to chloramphenicol.
Our study recorded fewer side effects in the chloramphenicol group than in the antibiotic tablet group, which is an important benefit. It is a general objective in general practice to minimise the use of systemic antibiotics, as this may reduce the development of resistance to antibiotics and cause fewer side effects in patients (17, 18).
Potential explanations as to why chloramphenicol eye drops are effective against conditions indicative of acute maxillary sinusitis, may be that they inhibit the growth of bacteria in the nasal cavity or that they dissolve a potential blockage that obstructs the sinus drainage tract. Normalisation of the sinus drain may be the immediate cause of rapid recovery, but it may also be that the local effect on the nasal mucous membrane is decisive. If this is the case, a chloramphenicol nasal spray may prove to be just as efficacious.
This pilot study had few participants, which makes the statistical calculations uncertain. It will also be difficult to achieve statistically significant differences between the groups being compared. Our results nevertheless show significantly faster recovery times for treatment with chloramphenicol eye drops compared to systemic antibiotics. However, the restricted scope of the study suggests that the outcomes should be interpreted with caution, and that the results should be tested in a larger randomised study. Because the treatment of sinusitis with chloramphenicol eye drops involves an entirely new principle, further trials should be of great interest. If the results of our pilot study can be confirmed, we will have an efficacious and inexpensive treatment option involving few side effects for patients with symptoms indicative of acute maxillary sinusitis.