Effect of dosage form and formulation factors on the adherence of drugs to the esophagus.

In recent years, many case reports concerning esophageal injuries caused by drugs have been published. The primary cause has apparently been the adherence of the drug product to the esophagus. In the present study, the adherent tendency of a number of types of tablets and capsules were tested in vitro using a recently developed isolated porcine esophagus preparation. The results showed that the tendency of products to adhere to the esophageal mucosa can be modified to a great extent by shape and formulation. Products with low adherence can be obtained by film coating with aqueous dispersions or by sugarcoating. In contrast, gelatin capsules and some cellulose films appear to have a high tendency to adhere to the esophagus.