Intestinal folate absorption in methotrexate treated psoriatic patients.

Thirty-one psoriatic patients 14 of whom were being treated with methotrexate (MTX), participated in a controlled study to evaluate the influence of MTX therapy on the intestinal absorption of folate. Low serum and red cell folate levels in the MTX treated group confirmed previously reported findings. However, analysis of the intestinal absorption profile yielded no significant difference between the two groups. It was concluded that MTX therapy for psoriasis does not adversely affect the intestinal absorption of folate and the observed low body folate status is probably mainly the result of enhanced renal excretion.