Drug absorption in celiac disease

Published evidence on established and theorized effects of celiac disease on drug absorption and pharmacokinetics is reviewed.

Patients with celiac disease develop a variety of gastric disorders requiring oral medications, but the impact of damage to intestinal villi and other celiac disease sequelae on drug absorption remains poorly understood. A review of the pertinent literature (English-language articles on research in adults published during the period 1970-August 2012) identified several reports of altered drug absorption mechanisms in patients with celiac disease, including accelerated or delayed gastric emptying, increased permeability of jejunal mucosa, changes in intraluminal pH, decreased intestinal surface area, and reduced intestinal cytochrome P-450 enzymes. A small number of published studies suggest that celiac disease may be associated with altered drug absorption, resulting in higher serum concentrations of propranolol, lower peak concentrations of acetaminophen and practolol, higher dosing requirements with levothyroxine, impaired or delayed absorption of certain antibiotics, and other pharmacokinetic effects with a potential impact on medication efficacy and toxicity. However, these studies involved very small patient samples and were poorly controlled, with some yielding contradictory results. More and larger pharmacokinetic studies in patients with celiac disease-especially studies of drugs that are dosed empirically or are not amenable to dosage adjustment according to vital signs or laboratory values-are needed.

Given the sometimes conflicting data on drug absorption in the context of celiac disease, cautious medication selection, dosage adjustment, and monitoring for efficacy and potential adverse effects are advised.