Does stress influence ampicillin concentration in serum and tissues?

Exercise produces changes of drug levels in plasma and increases the concen tration of free fatty acids (FFAs), which may interfere with drug-protein b inding. FFAs seem to play an antagonistic role to drugs since they have a s trong binding capacity to serum albumin. The aim of this study was to evalu ate the influence of the consecutive exercise-induced stress in ampicillin levels. Two groups of Wistar rats were used. Group A consisted of six subgr oups that were subjected to cold swimming (4 degreesC) for 5, 10, 15, 20, 2 5, 30 days respectively. Group B was the control group. The animals were in jected im. with ampicillin (1 g/Kg/8h in 5 doses). Results showed that exer cise enhanced stress parameters (FFAs, adrenal weight, Ht%) and led to an a mpicillin increase in all experimental groups comparatively to controls.