A-25 Disease Interactions

Vitamin A (including beta-carotene) is fat soluble and requires bile for adequate intestinal absorption. Hepatic and/or biliary dysfunction decrease the absorption of vitamin A. Vitamin A is metabolized by the liver and primarily excreted in bile and feces. Beta-carotene is primarily metabolized in the GI mucosa to vitamin A. Hepatic and/or biliary impairment can alter the metabolic and therapeutic activity of Vitamin A.

Absorption of vitamin A depends on the presence of bile and absorbable fat in the GI tract. Prolonged fat malabsorption (cystic fibrosis, hepatic cirrhosis, sprue) or malabsorption syndromes (celiac disease, GI resection) can decrease the absorption of Vitamin A. Water- miscible vitamin A formulations may be an appropriate alternative in malabsorption conditions for certain conditions requiring vitamin A therapy.