Esophageal transit

The issue of surface properties in tablets is also important and, surprisingly, small flat tablets can cause problems. In the development of a risedronate product, we needed to develop a procedure that was able to discriminate between alternative formulations. The key conditions necessary to differentiate among products with respect to the ease of swallowing was to dose the unit with one mouthful of water—30 mL. Using this procedure we demonstrated that small, uncoated, shallow convex-shaped tablets (9.5 mm diameter) were arrested in the esophagus more often than the final design of the formulation—an oval of 5.7 x 11.5 mm (2). In 5 out of 30 cases, esophageal transit of the smaller tablet was slower (6). 

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KS Channer, CJC Roberts. Effect of delayed esophageal transit on acetaminophen absorption. Clin Pharmacol Ther 37 72-76, 1985. 

JT Fell. Esophageal transit of tablets and capsules. Am J Hosp Pharm 40 946-948, 1983. 

Perkins, A. C., Wilson, C. G., Frier, M. et al., The use of scintigraphy to demonstrate the rapid esophageal transit of the oval film-coated placebo risedronate tablet compared to a round uncoated placebo tablet when administered with minimal volumes of water, Int. J. Pharm. 2001, 222, 295-303. 

Perkins AC, Wilson CG, Frier M, Vincent RM, Blackshaw PE, Danserau RJ, Juhlin KD, Bekker PJ, Spiller RC. Esophageal transit of risedronate cellulose-coated tablet and gelatin capsule formulations. Int J Pharm 1999 186 169-175. 

In this technique, a radio-opaque material has to be incorporated in the DF, and its location is tracked by X-ray pictures. The technique is used to evaluate gastroretentivity of GRDFs and the disintegration rate of DFs in vivo, and also to determine the esophageal transit. Although it is considered cheap and a simple method to use, its major disadvantage is the safety issue owing to repeated exposure to X-ray that increase the risk for the volunteers. ... 

Esophageal transit time is adversely affected by various disease states, for example, achalasia ° scleroderma, esophageal carcinoma, Barrett s esophagus. 

It is commonly assumed that swallowed dosage forms pass without hindrance into the stomach unless an underlying esophageal condition is present. However, it has been shown that esophageal transit of capsules or tablets is strongly influenced by the volume of the coswallowed water and the body position [15, 16]. 

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