Optic neuritis chloramphenicol

Optic neuritis (chloramphenicol and NSAIDs may show a papillitis)... 

The optic nerve is of interest here because some drugs are toxic to this tissue.The antibiotics chloramphenicol, ethambutol, streptomycin, and sulfonamides can cause optic neuritis. Vitamin A, especially in large doses, can result in papilledema. Digitalis can cause retrobulbar neuritis (see Chapter 35). 

Visual impairment associated with chloramphenicol therapy usually recovers after the drug is discontinued, but pretreatment visual acuity is often not regained and visual field defects may persist. Some patients may tolerate further prolonged treatment with chloramphenicol without recurrent optic neuritis, and, occasionally, patients can demonstrate improvement of visual function despite continued therapy. 

Most cases of optic neuritis associated with chloramphenicol therapy have occurred in children with cystic fibrosis who were treated with large daily dosages of the... 

The precise mechanism by which chloramphenicol produces optic neuritis is unknown.Although the view is not substantiated, several authors have proposed that chloramphenicol may induce optic neuropathy by causing a vitamin deficiency. Genetic fectors may be involved, and it has also been hypothesized that chloramphenicol may be biotransformed into degradation products that are potentially toxic to the optic nerve. 

Retrobulbar optic neuritis and polyneuritis have been attributed to prolonged chloramphenicol therapy (12). 

Murayama E, Miyakawa T, Sumiyoshi S, Deshimaru M, Sugita K. [Retrobulbar optic neuritis and polyneuritis due to prolonged chloramphenicol therapy.] Rinsho Shinkeigaku 1973 13(4) 213-20. 

Venegas-Francke P, Fruns-Quintana M, Oporto-Caroca M. Neuritis optica bilateral por cloranfenicol. [Bilateral optic neuritis caused by chloramphenicol.] Rev Neurol 2000 31(7) 699-700. 

Beyer CR. Chloramphenicol-induced acute bilateral optic neuritis in cystic fibrosis. J Pediatr Ophthalmol Strabismus 1978 15 291. 

Chloramphenicol may cause retinal bleeding (as a symptom of aplastic anaemia), alterations in the perception of colours, and optic neuritis. The latter type of side effect has been observed especially in children with cystic fibrosis receiving chloramphenicol in relatively high doses for fairly long periods (38 ). Deficiency of B vitamins is believed to be the cause of the optic neuritis, and perhaps also of the polyneuritis, peripheral neuritis, and paraesthesiae of the legs sometimes seen after prolonged courses of treatment with chloramphenicol and thiam-phenicoL Administration of extra vitamins may protect patients from this type of reversible side effect (SED VIII, p. 610 38 ). 

Adverse effects include gastrointestinal upset which tends to be mild. Optic and peripheral neuritis occur with prolonged use (which should be avoided) but are uncommon. The systemic use of chloramphenicol is dominated by the fact that it can cause rare (between 1 18 000-100 000 courses) though serious bone marrow damage. This is of two types ... 

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