Possible association between ocular chloramphenicol and aplastic anaemia—the absolute risk is very low
Article first published online: 4 JAN 2002
British Journal of Clinical Pharmacology
Volume 46, Issue 2, pages 181–184, August 1998
How to Cite
Laporte, J.-R., Vidal, X., Ballarín, E. and Ibáñez, L. (1998), Possible association between ocular chloramphenicol and aplastic anaemia—the absolute risk is very low. British Journal of Clinical Pharmacology, 46: 181–184. doi: 10.1046/j.1365-2125.1998.00773.x
- Issue published online: 4 JAN 2002
- Article first published online: 4 JAN 2002
- aplastic anaemia;
Aims To determine whether topical ocular chloramphenicol increases the risk of aplastic anaemia and to estimate the magnitude of this risk, if any.
Methods Population-based prospective case-control surveillance of aplastic anaemia in a community of 4.2 million inhabitants from 1980 to 1995 (67.2 million person-years) plus case-population estimate of the risk, based on sales figures of ocular chloramphenicol in the study area during the study period.
Results One hundred and forty-five patients with aplastic anaemia and 1,226 controls were included in the analysis. Three cases (2.1%) and 5 controls (0.4%) had been exposed to ocular chloramphenicol during the relevant etiological period. The adjusted odds ratio was 3.77 (95% confidence interval, 0.84–16.90). Two cases had also been exposed to other known causes of aplastic anaemia. The incidence of aplastic anaemia among users of ocular chloramphenicol was 0.36 cases per million weeks of treatment. The incidence among non users was 0.04 cases per million weeks.
Conclusions An association between ocular chloramphenicol and aplastic anaemia cannot be excluded. However, the risk is less than one per million treatment courses.