Mental health care in Brazil is undergoing transformations, with the implementation of the Psychosocial Care Centre (CAPS), which represents the axis of the psychosocial network, replacing the hospital-centric model. As a consequence of the transformation of this model, it was necessary to review the training of CAPS professionals, since there is a notorious lack of continuing education in the field of mental health. The aim was therefore to assess the effectiveness of the training of professionals working in the Caps who had completed the refresher course on drugs. This is a descriptive and exploratory study with a qualitative, cross-sectional approach. The data was analysed using content analysis and the following Thematic Categories were defined: 1 - Attitudes and beliefs; 2 - Specific knowledge; 3 - Good practices and; 4 - Training. The sample consisted of eight professionals, 75 per cent of whom were male, with a predominance of professionals with a university degree. The evaluation of the effectiveness of professional training shows positive aspects in terms of the practice of caring for users and their families, with a view to establishing a bond with the service.