Paracetamol absorption test with Wagner-Nelson analysis for safe and accurate measurements of gastric emptying in women.

The physiological and pharmacological aspects of gastric emptying in fertile or pregnant women have been studied. Scintigraphy is the reference method for measuring gastric emptying. However, it should be applied very cautiously to women of childbearing age because of the risk of substantial irratiation. In such a population, paracetamol absorption has been used safely as an index of gastric emptying, but its accuracy has been challenged. The Wagner-Nelson method is a traditional tool used to precisely evaluate drug absorption kinetics. To clarify whether the absorption kinetics of paracetamol assessed by the Wagner-Nelson method is as accurate as scintigraphy in evaluating gastric emptying in young women, gastric emptying of a 200-kcal liquid meal was measured simultaneously by scintigraphy and the paracetamol test in 10 healthy young female volunteers. Paracetamol absorption systemically overestimated the rate of gastric emptying measured by scintigraphy. By introducing a correction factor into the paracetamol test, the overestimation could be adjusted. The paracetamol test with Wagner-Nelson analysis can be a safe and accurate method for measuring gastric emptying in women of childbearing age.