Comparison of dose-related ocular side effects during systemic isotretinoin administration.

PURPOSE To compare the effects of high- (Group 1) and low-dose (Group 2) isotretinoin treatments for acne vulgaris on lacrimal functions and other ocular complications. METHODS Twenty-six patients receiving high-dose (>0.5 mg/kg per day) systemic isotretinoin treatment and 25 patients treated with low-dose systemic isotretinoin (<0.5 mg/kg per day) underwent complete ophthalmologic assessment of both eyes before treatment, at days 45 and 90 of treatment, and 1 month after the completion of treatment, together with a microbiologic evaluation of conjunctival flora, tear film break-up time (BUT), and anesthetized Schirmer test of the right eye of each patient. RESULTS When the results of the anesthetized Schirmer test for Groups 1 and 2 were compared (pretreatment, days 45 and 90 of treatment, and 1 month after treatment), there was no statistically significant difference between the groups (p > 0.05). Although BUT did not differ significantly between the two groups before treatment (p >0.05), there was a statistically significant decrease in BUT in Group 1 when compared with Group 2 at days 45 and 90 of treatment (p <0.05). One month after the completion of treatment, there was no difference in BUT between the two groups (p >0.05). No difference in Staphylococcus aureus colonization was detected between the two groups at days 45 and 90 of treatment (p >0.05). CONCLUSIONS During systemic isotretinoin treatment, eye dryness was related to the dose used, at least during the period of treatment. Conversely, the rate of conjunctival S aureus colonization was unrelated to the dose of isotretinoin.