To the Editor.—
In regard to the report by Leavell and Yarbro of "Hydroxyurea: A New Treatment for Psoriasis" (Arch Derm 102:144-150, 1970), I was disappointed that they did not make specific reference to some of the studies of other cytotoxic agents in the treatment of psoriasis. Purine analogues,1-3 alkylating agents2,3 and other antimetabolites4 have been reported to be effective in psoriasis. Thus, the question is whether hydroxyurea has a better therapeutic index and less side effects in the treatment of psoriasis compared with these other cytotoxic drugs. A comparison study would be of interest. I share the feeling of the authors that there may be better, safer drugs than methotrexate in severe psoriasis.