The Effect of Anticonvulsant Therapy upon the Absorption of Folates

Abstract

1. The absorption of orally administered pteroylmonoglutamate and pteroyltetraglutamate, measured as peak rise in serum folate levels, was examined in normal volunteers and in epileptic patients on anticonvulsant drugs. 2. Although the fasting serum folate levels were low in the patients, they absorbed the two folate forms as well as the volunteers did and there was no difference between the absorption of pteroylmonoglutamate and pteroyltetraglutamate. 3. The findings indicate that the folate deficiency, caused by anticonvulsant drugs is not due to interference with the intestinal conjugase or the mechanism of absorption in itself.

Effect of anticonvulsant drugs on the rate of folate catabolism in mice.

“…Malabsorption of folate has been reported to occur (4-6) but has not been confirmed (7)(8)(9)(10)(11).…”

Folic Acid Absorption Test in Various Clinical Conditions

“…The relatively high incidence of abnormal 5-hour glucose tolerance curves in our patients with folate-responsive neuropsy chiatrie symptoms raised the question of the relationship between folate and carbohydrate metabolism [1], There have been positive [6,9,12,16] and negative studies [10,17] regarding the effects of diphenylhydantoin (DPH) on folate ab sorption in humans. It is, however, generally accepted that DPH inhibits folate absorption at the intestinal level [9], Therefore, we considered it useful to carry out a folate absorption test in the following groups of subjects: normal controls, patients with disorders of carbohydrate metabolism, epileptic patients receiving DPH, patients with gastroduodenal disease and patients with atrophy of jejunal mucosa.…”