Understanding clinical toxicology and poisoning
Clinical toxicology covers diagnosis, management and prevention of poisoning and overdose. Assessment integrates exposure history (substance, formulation, route, dose and time), examination pattern (toxidrome), and targeted tests—including serum drug levels only when results change decisions. WHO chemical safety frameworks, nationally designated poison centres and regional protocols (examples: NICE in the United Kingdom, EAPCCT networks in Europe, coordinated poison-centre networks in other regions) inform decontamination, antidote stewardship and enhanced elimination.
Routes (oral, inhalational, dermal, ocular, injection) shape onset and interventions; pharmacokinetics (including formulation delays—modified-release, transdermal) informs prognosis and observation periods. Supportive care is universal—airway, breathing, circulation, seizure control, correction of hypo-/hyperglycaemia and acid–base disturbances—alongside substance-specific therapy where evidence supports it.
Nursing overlaps with renal (fluid shifts, extracorporeal therapy where indicated), hepatic (e.g. paracetamol injury pathways), neurological (altered consciousness), cardiorespiratory (rhythm, ventilation), mental health (safeguarding after deliberate overdose), infectious/environmental medicine when exposures overlap outbreaks or contaminants.
Core concepts in poisoning care
Decontamination indications vary internationally—activated charcoal in narrow windows for adsorbable ingestions when airway protected; eye/skin irrigation after splash exposures; whole-bowel irrigation only when guideline-supported; gastric lavage highly selective early-window scenarios per policy.
🚨 Toxicology red flags — escalate immediately
- Airway compromise or refractory hypoventilation (opioids, sedatives, corrosive injury)
- Haemodynamic collapse or malignant dysrhythmia (sympathomimetics, cardioactive toxins)
- Recurrent seizures, declining Glasgow Coma Scale, or signs of intracranial catastrophe
- Suspected toxic alcohol ingestion with metabolic acidosis / elevated osmolar gap patterns when measured locally
- Paracetamol (acetaminophen) overdose where threshold criteria for antidote are met—timing-critical
- Caustics, inhalational burns with stridor, or button batteries ingested—urgent speciality pathways per protocol
Rapid Assessment Pathways
Opioids / CNS depression
- Miosis (often), hypoventilation, sedation ladder
- Naloxone where indicated—titrate to ventilation
- Observe prolonged respiratory depression after reversal—half-life mismatch
- Mixed ingestions—avoid risky reversal sequences when benzodiazepines/co-ingestants
Sympathomimetic tox
- Agitation, tachycardia, hypertension, hyperthermia
- Benzodiazepines first-line for seizure/agitation; cooling
- Avoid unopposed beta-blockade after sympathomimetic exposure patterns
- ECG—ischaemia, prolonged QT—observe escalation criteria
Anticholinergic pattern
- Dry flushed skin, mydriasis, urinary retention, delirium
- Supportive care—avoid unnecessary restraint when intoxicated
- Physostigmine exceptionally selective settings—consult poison specialists
- Rule out alternative diagnoses mimicking pattern
Paracetamol / delayed hepatopathy
- Reliable time and formulation history—acute vs staggered exposures per guideline
- LFTs/INR may lag early—follow institution pathway
- Acetylcysteine where indication thresholds met—regimen per formulary
- Escalate for hepatic failure patterns—critical care & transplant pathways locally
Toxicology-related symptoms
Toxicology conditions
Nursing procedures
Diagnostic tests
Toxicology medications
Related Body Systems
▶ References & Guidelines
- World Health Organization (WHO). Poisoning and chemical safety.
- European Association of Poisons Centres and Clinical Toxicologists (EAPCCT). Clinical toxicology resources.
- National Institute for Health and Care Excellence (NICE). Guidance (including acute poisoning).
- American Association of Poison Control Centers (AAPCC). Poison centre network (United States example).
- British Toxicology Society (BTS). Toxicology education.
- Centers for Disease Control and Prevention (CDC). Environmental health.
Explore the full Medical Library
Browse all systems, conditions, symptoms, procedures, tests, and medications across the NurseOnShift clinical reference library.
Open Medical Library→