An integrating and dynamic model of personality that allows predicting theresponse of the basic factors of personality, such as the Big Five Factors (B5F)or the general factor of personality (GFP) to acute doses of drug is presentedin this paper. Personality has a dynamic nature, i.e., as a consequence of astimulus, the GFP dynamics as well as each one of the B5F of personalitydynamics can be explained by the same model (a system of three coupleddifferential equations). From this invariance hypothesis, a partial differentialequation, whose solution relates the GFP with each one of the B5F, is deduced.From this dynamic approach, a co-evolution of the GFP and each one of the B5Foccurs, rather than an unconnected evolution, as a consequence of the samestimulus. The hypotheses and deductions are validated through an experimentaldesign centered on the individual, where caffeine is the considered stimulus.Thus, as much from a theoretical point of view as from an applied one, themodels here proposed open a new perspective in the understanding and study ofpersonality like a global system that interacts intimately with the environment,being a clear bet for the high level inter-disciplinary research.