Clinical Presentation and Management of Ethoxy-Modified Trisiloxane Surfactant Poisoning.

Suicidal attempts involving herbicide ingestion are extremely rare in Macao. We report the case of a 13-year-old Chinese female student with a history of mental disorder who presented to the emergency department (ED) of Conde S. Januário Hospital (CHCSJ) after intentionally ingesting 30-40 mL of a herbicide containing ethoxy-modified trisiloxane, a compound with limited human toxicity data that warrants clinical attention. On admission, she was asymptomatic and hemodynamically stable, with unremarkable physical examination and laboratory findings. She was admitted for observation. During her stay, she reported only mild abdominal discomfort, which was managed symptomatically. After 20 hours of observation, she remained stable and was discharged with outpatient psychiatric follow-up arranged. This case underscores that even with potentially toxic herbicides, prompt medical assessment and supportive care can lead to a positive outcome, while highlighting the critical need for psychiatric intervention in cases of intentional self-harm.