Respuesta analgésica y seguridad del uso de metadona en pacientes con dolor oncológico de difícil control atendidos de julio a diciembre del 2025 en el Hospital SOLCA Guayaquil.

Abstract

Cancer pain of difficult control represents a significant clinical challenge due to its heterogeneous nature and limited response to conventional opioids. This research analyzes the analgesic response and safety of methadone, a synthetic opioid with a dual mechanism of action (mu-agonist and NMDA antagonist), in patients treated at Hospital SOLCA-Guayaquil. Method: An observational, retrospective cohort study was conducted on 60 adult patients treated with methadone between Jule and december 2025. Pain intensity was evaluated using the Visual Analog Scale (VAS) at baseline, 72 hours, and 7 days, defining "analgesic response" as a reduction of at least 2 points by the seventh day. Results: The sample had a median age of 54 years, with a predominance of females (66.7%) and mixed-type pain (51.7%). Pain intensity decreased significantly from a baseline median of 8 to 3 points at 72 hours and to 2 points on the seventh day (p < 0.001). Overall, 95% of patients achieved a satisfactory analgesic response. Only 1.7% reported mild adverse events, with no serious complications recorded. A significant association was found between active chemotherapy and a higher response rate (p < 0.05). Conclusions: Methadone is an effective and safe alternative for managing refractory cancer pain in the local setting, achieving relevant clinical relief in the vast majority of cases with a minimal incidence of undesired effects..