This 6-month study evaluated a probiotic multivitamin preparation in 42 adult men and women suffering from stress or exhaustion. The preparation was taken daily with breakfast. A psychological-neurologic questionnaire assessed psycho-organic, central vegetative, and somatic discomforts, and a validated list of adjectives was used to indicate the effect of therapy. At the end of the study, an overall 40.7% improvement in stress was noted, representing significant improvements of 17.4% in positive conditions and of 23.3% in negative conditions (both P<.001). In addition, decreases of 29% in the frequency of infections and of 91% in gastrointestinal discomforts, both established indicators of stress, were recorded. The preparation was well tolerated. This probiotic multivitamin is suitable for reducing stress or exhaustion, or both, as well as for improving the immune system, specifically gastrointestinal health.