INTRODUCTION:
The Brazilian Psychiatric Reform and the Psychosocial Care Network (RAPS) have established Primary Health Care (PHC) as the central axis of mental health care within the Brazilian Unified Health System (SUS)⁴,⁵,⁶,¹⁸. In the context of increasing psychological distress, a shortage of specialized professionals, and persistent inequalities in access to care, mental health matrix support has emerged as a technical, educational, and care-oriented strategy to promote equity and improve care delivery ⁹,¹¹,¹⁶,²¹.

METHODS:
This cross-sectional, exploratory study used a qualitative approach with participant observation and was conducted in a municipal health center. The study was approved by the Research Ethics Committee of the Federal University of São Carlos (UFSCar) ³,⁷,⁸. Data collection included field notes and a semi-structured questionnaire administered to PHC physicians, followed by descriptive data analysis.

RESULTS:
Sixteen professionals participated, most of whom were Family and Community Physicians, primarily affiliated with the More Doctors Program. Matrix support was implemented in response to unmet demand and the shortage of psychiatrists, through monthly meetings that included shared consultations and case discussions¹³,²⁰. This strategy enhanced professional training, strengthened longitudinal care, improved clinical competencies, and expanded the biopsychosocial perspective, contributing to more inclusive, shared, and effective care ²,¹⁰,¹⁹. Limited integration with the multiprofessional team was identified as a key challenge¹,¹⁷.

CONCLUSIONS:
Mental health matrix support improves the quality of PHC, expands access to care, promotes inclusion, and strengthens mental health care within the SUS. Ongoing investment in interdisciplinary collaboration and continuous professional development is essential to ensure sustainable and equitable mental health care in PHC¹²–¹⁵.