Separation Anxiety (SA) is a behavioral syndrome that may affect dogs of different ages and that is characterized by intense clinical signs. Traditional veterinary clinic efforts rely on harmful side effect drugs. Overall, homeopathy handles individual idiosyncrasies and susceptibilities and deal with them using a single medicine through the law of similarity. This study aimed to determine whether individualized homeopathic medicines have a greater effect than placebo for dogs suffering from SA or not, assessing its relation to behavioral settings, cortisol levels, and blood cells count before and after therapy. It also focused on setting a demographic profile of these dogs. Owners filled out a score questionnaire. Twenty-one dogs were recruited and repertorized in accordance to classical homeopathy. A pharmacist was responsible to randomize and dispense verum medicine or placebo. On the 30th day, reappraisal of owners were allowed altering the dispensed medicine. The final assessment occurred on the 60th day. In verum group, destructive behavior analysis had a significant statistical difference intra-group over the trial compared to the placebo group. The mean of cortisol levels in the placebo group was significantly higher on the 60th day of the trial when compared to the verum group, whose levels were sustained over the same period. Although evidenced behavioral improvements could be related to homeopathic preparations, it was not feasible to set any connection between homeopathic interventions, behavioral issues, and plasma components
