Toxidromes

Poisoning is an important and prevalent concern, occurring owing to many drugs, chemicals or natural poisons. Prompt diagnosis and treatment optimize outcomes. Initial management involves concurrently assessing the history of exposure, performing a clinical examination and resuscitation when required. The integration of symptoms and clinical signs, and possibly investigations and/or the response to an antidote, can enable the identification of a potential toxidrome. Toxidromes are important in the assessment and management of patients with poisoning. Each toxidrome may be caused by a particular group of poisons, so diagnosis of a toxidrome may indicate what a patient was exposed to, guiding further clinical assessment and management. Identifying a toxidrome can be especially informative when a history cannot be obtained, for example in patients who are drowsy or extremely agitated. Additionally, a toxidrome may help to confirm the accuracy of the history of exposure, when this is available, facilitating further assessment and management. Classic poisoning-related toxidromes include the opioid, sympathomimetic, serotonergic, antimuscarinic, muscarinic and nicotinic toxidromes. Other toxidromes that are common and require careful clinical consideration include bradycardia with hypotension, 'knockdown', mushroom poisoning, neuroleptic malignant and uncoupling of oxidative phosphorylation syndromes. Multiple toxidromes can occur together following exposure to certain single xenobiotics or to multiple xenobiotics, which can complicate clinical decision-making. Future directions include refining diagnostic tools including bedside and/or laboratory investigations to complement clinical assessments, improving access to region-specific toxidrome data, and developing targeted therapies to enhance outcomes and address current gaps in care.