[Study of the acid buffering capacity of dietary components regarding food-drug interactions]

Food intake is known to exert numerous effects on drug pharmacokinetics through a variety of mechanisms, and for some medicinal compounds, food-drug interaction could prove of crucial clinical importance. As for acid-labile drugs, bioavailability studies performed in both fasting and fed states are considered essential. A simple and fast in vitro procedure using the USP Dissolution Apparatus II (paddle method) was applied to study acid buffering capacity of food components under simulated in vivo environment. As expected, carbohydrates (starch, sugars) and fat (oil emulsions) failed to show considerable acid buffering capacities, while protein-containing components (milk powder, gelatine) showed significant acid buffering capacity. The results of an in vitro model applying the so-called "standard meal" were in correlation with data obtained from studies performed in healthy volunteers. Nevertheless, in vitro models simulating both the fed and the fasting states in the GIT help explore factors related to food effect on drug dissolution; and consequently, achieve better insight into postprandial drug behaviour.