Abstract
ICR mice were grouped according to 1) housing environment: individual (I) or aggregated (A) and 2) timing of drug administration: midlight (L) or middark (D), i.e. I-L, I-D, A-L, A-D groups. Theophylline was orally administered at midlight or middark. The results showed that both social environment and timing of drug administration exerted significant influence on the pharmacokinetics of theophylline. These data may suggest the importance of considering many non-drug factors in toxicological studies with experimental animals.
