[Drugs and assessment of gastrointestinal motility]

Any determination of gastrointestinal motility is based on two assumptions: (1) That the patient is examined in "physiological" conditions and (2) that the values measured truly reflect the parameter the investigator wishes to examine. A large array of very different drugs shares the ability to modify the digestive motility (i.e. gastrokinetics) or to alter the content of the digestive tube in such a way that it affects the outcome of some measurements (i.e. acid suppression leads to false results in ph-metry dependent methods). Therefore, it seems advisable to ask the patient whether he is taking any drug--including non prescription medications--and check if this substance or type of substances could affect the outcome of the motility measurement envisioned. In this paper, the authors present a list of the principal drugs known to affect different motility-measurement methods. The real or apparent stimulating or inhibitory effects of drugs on four main segments of the digestive tube (esophagus, stomach, small intestines and colon) are indicated in an alphabetically ordered table. In a short review, the drugs are broadly classified according to their mechanism and site of action. Besides a number of drugs used in practice because of their action on the enteric nervous system, there is a large spectrum of compounds affecting motility, whose main therapeutic application lies outside the digestive tract, such as: psychotropic drugs, antiparkinsonian drugs, bronchodilators, antitussives, antihistamines, antimigraine drugs, antihypertensive agents, etc. This second category is more likely to escape unnoticed as a potential source of false results in the measurement of digestive motility.