Vitamin A Supplementation for Retinitis Pigmentosa-Reply

In reply  In our editorial¹ on vitamin A supplementation as a treatment for RP,² we discussed three major areas of concern: (1) the study did not demonstrate significant benefit for any measure of visual function; (2) the significant effect observed with the cone ERG has additional explanations not related to slowed progression of the disease; and (3) the long-term systemic and/or toxic effects of supplemental vitamin A are unknown. The arguments presented by Dr Berson and colleagues in response to our editorial restate points made in their article and provide some new unpublished information, but they do not satisfy our principal concerns.The reaffirmed recommendation of the authors of the clinical trial is that "most adults with the common forms of RP [should] take 15 000 IU/d of vitamin A under the supervision of their ophthalmologist and avoid high-dose supplementation with vitamin E such as the 400 IU/d used