Neurological and neurophysiological effects of oral isotretinoin: a prospective investigation using auditory and visual evoked potentials.

Over the last decade, accumulating evidence has indicated that retinoids may be capable of affecting the development, differentiation and function of nervous tissue. The purpose of the present study was to investigate whether oral isotretinoin can affect brainstem and cortical sensorial activities. We performed neurological and neurophysiological studies (brainstem auditory and visual evoked potentials) in 32 patients with various skin diseases receiving isotretinoin. A significant increase of the third (L(III)) and fifth peak latency (L(V)) in left and right ear (p = 0.03, p = 0.02 for L(III), p = 0.03, p = 0.04 for L(V) respectively), and a significant increase in the latency of wave one and interpeak latency (IPL) I-V in the left ear were found after isotretinoin administration, as compared to the pretreatment (p = 0.0036 and p = 0.02, respectively). No significant differences of other latencies, IPLs and the value of visual evoked potential P-100 implicit time were observed. However, a marked increase in latency P-100 wave was found in 6 patients after therapy. It seems reasonable to suggest that neurophysiological and neurological evaluation of audiological and ocular nerve (or retinal) function may be added to the list of investigations that are performed in patients treated with oral isotretinoin.