Azulfidine-induced oligospermia.

A patient with Crohn's ileitis was treated with azulfidine (4 gm./day) for 18 months. During the treatment period he was infertile with quantitative and qualitative abnormalities of his spermatozoa. Upon termination of the azulfidine, his semen analysis became normal and his wife subsequently became pregnant. In some patients there appears to be an effect of azulfidine on spermatogenesis that is completely reversible when the drug is withdrawn.