[Decomposition of chloramphenicol in eyedrops--irritation in the eyes]. / Spaltning av kloramfenikol i øyedråper--svie i øynene.

Chloramphenicol single dose eyedrops 0.5% (Nycomed Pharma) have been found to be very sensitive to exposure to light. We could detect approximately 15% decomposition after six hours of exposure to diffuse daylight. One of the decomposition products is the extremely irritant dichloroacetic acid. This may explain why some patients complain of a burning sensation in the eyes. In one of the samples of light yellow eyedrop received together with the complaints our analysis revealed 17% of the end-cleavage product p-nitrobenzaldehyde. The Norwegian Medicines Control Authority will suggest to the producers of these preparations that they market the product in special light-proof containers.

Review on crystal polymorphism of substances in the European pharmacopoeia.

Substances in the European Pharmacopoeia, reported as having polymorphism are reviewed. For these substances the analyst may expect irregular melting behaviour and IR spectra.