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OverviewAetiologyPathophysiologyClinical features and red flagsInvestigationsDifferential diagnosisManagementComplicationsMonitoring and follow-upSpecial situationsCommon pitfallsQuestionsSources
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Educational draft · awaiting clinical reviewThe full textbook explains uncertainty but does not replace live national or local guidance, specialist advice, or current prescribing information.

Poisoning and accidental ingestion

Paediatrics and child health · UK scope · Sources checked 27 Aug 2026 · Clinical review pending

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Toxic physiological compromise

Reduced consciousness, apnoea, seizure, severe agitation, shock, arrhythmia, QRS or QT abnormality, severe acidosis, hypoglycaemia, hyperthermia or rapidly progressive organ injury requires immediate resuscitation and specialist toxicology support.

Action: Protect staff from contamination, use ABCDE, give oxygen and early ventilatory support when required, check glucose and temperature, attach ECG and establish IV or IO access. Identify the product and maximum possible dose, consult current TOXBASE guidance, contact NPIS for a severe or complex case, and give a time-critical antidote or decontamination only when the substance-specific pathway supports it.

Overview

Stabilise a child with possible poisoning, obtain a precise exposure history without delaying care, use TOXBASE and the National Poisons Information Service as the UK decision standard, recognise toxidromes and high-risk substances, and integrate mental-health, medication-safety and safeguarding assessment.

Stabilisation and identification proceed together. Use ABCDE, check glucose and temperature and place a drowsy child where airway and ventilation can be supported immediately. In hypotension give 10 mL/kg isotonic crystalloid and reassess; toxic vasodilation or myocardial depression may need early noradrenaline or another toxin-specific strategy. Treat status epilepticus by the paediatric algorithm while consulting toxicology because some antidotes and antiarrhythmics are poison specific.

Construct the maximum possible exposure rather than accepting a reassuring estimate. Confirm the product name, active ingredients, strength, immediate or modified release, container size, tablets missing, time range, route and co-ingestion. Use current measured weight to calculate mg/kg. Ask who saw the event, whether the child could open the container, what was found at the scene and what treatment was given.

Practice

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Paediatrics and child healthOriginal SBA

UK toxicology decision support

A well toddler may have swallowed an unfamiliar grandparent's modified-release tablet. The amount is uncertain. What is the most appropriate next information source for the clinician?

Choose one answer, then submit
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Sources and review status4 sources · checked 27 Aug 2026 · clinical review pending+
Sources

Sources and review status

National guidance is shown before implementation-dependent detail. Typical adult dose examples remain subject to patient factors, contraindications and the live BNF or specialist protocol. Source check completed 27 Aug 2026; clinical approval remains outstanding.

  • National Poisons Information Service TOXBASEUK first-line clinical toxicology database, scope, access and escalation to specialist telephone advice.
  • Resuscitation Council UK 2025 Paediatric Life SupportABCDE toxicology support, ECG and laboratory assessment, shock care, poison-centre consultation and prolonged resuscitation principles.
  • MHRA intravenous acetylcysteine regimenAuthorised three-infusion 21-hour dosing and criteria to consider continued treatment.
  • NICE CG89 child maltreatment alerting featuresPoisoning, access, unsuitable explanation, repetition, deliberate administration and supervision-related safeguarding indicators.

Editorial contact: Doctor’s Passport editorial team. Source-check date is separate from clinical approval. Report a content problem · Content changes

Authoring stateComplete draftClinical stateAwaiting reviewJurisdictionUnited Kingdom
Examination looks for pattern and injury: pupils, secretions, skin moisture and colour, odour, bowel sounds, urinary retention, muscle tone, clonus, rigidity, fasciculation, needle or patch sites, tablet residue, burns and trauma. Record a 12-lead ECG with QRS and QTc in altered consciousness or suspected cardiotoxic ingestion. A toxidrome focuses management but mixed exposure and non-toxic illness remain possible.

Consult TOXBASE early because risk thresholds, sampling times, decontamination, observation and antidotes change by agent and formulation. It is the NPIS primary clinical database and the first port of call for UK healthcare professionals. Telephone NPIS when severe toxicity, an unusual product, pregnancy, mixed ingestion, difficult interpretation or a management decision exceeds the monograph.

Gastrointestinal decontamination is selective. Do not induce emesis. Activated charcoal may reduce absorption after some substantial recent ingestions, but it does not bind every poison and aspiration can be fatal. Use it only after a substance-specific recommendation, usually within one hour, when the airway is intact or protected. Corrosives, hydrocarbons and foreign bodies need their own pathway rather than generic lavage.

Paracetamol deserves deliberate timing. A plasma concentration taken before four hours after a single acute ingestion is not interpretable on the treatment nomogram. A timed result at or after four hours is assessed on the current UK line. If timing is uncertain, ingestion is staggered or presentation is late with sufficient concern, start acetylcysteine without delay and use TOXBASE to guide serial paracetamol, ALT, INR, creatinine, bicarbonate and continuation decisions.

The authorised IV acetylcysteine schedule remains 150 mg/kg over one hour, 50 mg/kg over four hours and 100 mg/kg over sixteen hours, total 300 mg/kg over 21 hours, with continued treatment at the third-bag rate when clinical and laboratory criteria require it. Some UK services use a TOXBASE-supported shortened SNAP protocol for eligible patients; the local approved pathway and weight or age exclusions must be followed rather than mixing regimens.

Safe discharge requires completion of the agent-specific observation and repeat tests, normal physiology, reliable supervision and a prevention plan. Review every medicine in the home, remove discontinued prescriptions, supply measuring syringes, separate sibling medicines and document locked storage advice. Intentional overdose needs age-appropriate privacy, mental-health assessment and a collaborative safety plan; safeguarding concern is shared through local child-protection procedures without accusatory interviewing.

Key points

  • Scene safety comes first for fumes, powders, pesticides and corrosives; remove contaminated clothing and use specialist decontamination advice without exposing staff.
  • First-line assessment is ABCDE, bedside glucose, core temperature, continuous observations and an early 12-lead ECG when consciousness, pulse or blood pressure is abnormal or a cardiotoxic agent is possible.
  • Record exact product, strength, formulation, time, maximum missing quantity, route, co-ingestants, symptoms, child's weight and pre-hospital treatment; bring packaging or a photograph.
  • TOXBASE is the first-line UK clinical toxicology resource for healthcare professionals; call NPIS for severe, unusual, mixed or uncertain cases.
  • Do not induce vomiting, give food or milk as a universal antidote, or attempt chemical neutralisation.
  • Activated charcoal is not routine: consider it only for a relevant toxic dose, usually within about one hour, after TOXBASE or NPIS advice and with a protected or reliably maintained airway.
  • Use substance-specific quantitative tests rather than a broad toxicology screen; many important poisons are missed by routine urine panels.
  • For a single acute paracetamol ingestion, measure plasma concentration at 4 hours or later; earlier levels cannot be interpreted safely.
  • Give acetylcysteine without delay for a staggered or uncertain-time paracetamol overdose or when the current treatment pathway indicates it; do not wait for liver injury.
  • Treat airway loss, seizures, hypoglycaemia, hyperthermia, electrolyte disturbance and shock while elimination occurs, and use a specific antidote only with a confirmed indication and dose.
  • Observation length and discharge are agent specific; a normal first examination does not override a delayed-toxicity window.
  • After stabilisation assess intent, developmental access, medicine storage, caregiver understanding, mental health, exploitation and safeguarding for the child and siblings.

Aetiology

01

Exploratory ingestion

Young children access unsecured tablets, liquids, nicotine products, household chemicals, plants or recreational substances and may not be able to report the event.

02

Therapeutic and administration error

Duplicate paracetamol products, decimal or concentration errors, sibling medicine, dosing by age rather than weight and repeated caregiver dosing can create toxicity without intent.

03

Intentional self-poisoning

Adolescents may take prescribed, over-the-counter or illicit substances during acute distress, sometimes with concealed co-ingestion or uncertain timing.

04

Environmental or inflicted exposure

Carbon monoxide, contaminated food or drink, pesticides and deliberately administered medicines require scene, household and safeguarding assessment beyond the individual child.

Pathophysiology

  1. 1
    Dose and kinetics

    Toxicity depends on absorbed dose per kilogram, formulation, time, co-ingestion, gastrointestinal motility and hepatic and renal elimination; modified-release products can delay the peak.

  2. 2
    Cellular and organ toxicity

    Agents may depress respiration, block myocardial channels, disrupt mitochondrial metabolism, injure liver or kidney or cause hypoglycaemia, seizures and hyperthermia.

  3. 3
    Toxidrome physiology

    Characteristic receptor effects produce patterns such as opioid respiratory depression, anticholinergic dryness and delirium, or cholinergic secretions and weakness, but mixed ingestions blur them.

  4. 4
    Paracetamol bioactivation

    When normal conjugation pathways saturate, the reactive metabolite NAPQI depletes glutathione and causes hepatic necrosis; acetylcysteine restores detoxification most effectively when given early.

Clinical features and red flags

Opioid pattern

Reduced respiratory rate and consciousness with small pupils suggests opioid effect, but hypoxia, clonidine and pontine disease can overlap.

Anticholinergic pattern

Agitation, mydriasis, dry flushed skin, tachycardia, urinary retention and reduced bowel sounds suggest muscarinic blockade.

Cholinergic pattern

Salivation, lacrimation, bronchial secretions, diarrhoea, small pupils, weakness and fasciculation suggest organophosphate or related exposure.

Serotonin toxicity

Agitation, hyperreflexia, inducible or spontaneous clonus and hyperthermia after serotonergic exposure distinguishes it from simple anxiety.

Cardiotoxic pattern

Syncope, hypotension, broad QRS, prolonged QT, bradycardia or ventricular dysrhythmia requires continuous monitoring and urgent NPIS advice.

Red flags requiring action

  • A single tablet of some adult medicines can be dangerous to a small child; apparent small quantity is not reassurance until product strength and weight-based dose are confirmed.
  • Bradycardia or tachycardia, hypotension, broad QRS, prolonged QT, ventricular ectopy or syncope requires continuous cardiac monitoring and toxin-specific advice.
  • Pinpoint pupils with slow breathing, anticholinergic agitation, serotonergic clonus, cholinergic secretions or sympathomimetic hyperthermia provides a toxidrome clue but does not prove one agent.
  • A child can initially appear well after paracetamol, modified-release medicine, sulfonylurea, calcium-channel blocker or some toxic alcohol exposures; disposition follows the substance, dose and observation window.
  • Staggered, uncertain-time or delayed paracetamol ingestion cannot be interpreted on the standard timed nomogram and may need acetylcysteine before results return.
  • Unexpected access in a non-mobile child, repeated episodes, an unsuitable explanation, unexplained drug levels or deliberate administration requires safeguarding action.
  • Any intentional ingestion needs a compassionate psychosocial and suicide-risk assessment after medical stabilisation, including access to medicines and immediate safety.

Investigations

  1. 01
    First-line bedside glucose, observations and temperatureFirst stepFirst line
    Why
    Find immediate reversible physiological threats and provide a toxicity trend.
    Interpretation and limitations
    Repeat glucose after correction and during observation for agents that cause delayed hypoglycaemia.
  2. 02
    First-line 12-lead ECGFirst line
    Why
    Detect sodium-channel blockade, QT prolongation, bradyarrhythmia or ischaemic and electrolyte effects.
    Interpretation and limitations
    Repeat after treatment and at the toxin-specific interval; a normal early ECG does not close every delayed-risk pathway.
  3. 03
    Electrolytes, renal and liver profile, gas and lactate
    Why
    Identify acidosis, organ injury, electrolyte change and dose-modification needs in a symptomatic or significant exposure.
    Interpretation and limitations
    Select and repeat tests according to the toxin; an elevated lactate has multiple causes and does not name the agent.
  4. 04
    Timed plasma paracetamol concentration
    Why
    Determine acetylcysteine need after a known single acute ingestion.
    Interpretation and limitations
    Sample at four hours or later and use the current UK treatment line; do not use the nomogram for staggered or uncertain timing.
  5. 05
    Substance-specific quantitative assay
    Why
    Measure salicylate, alcohol, iron, anticonvulsant or another agent when the result changes treatment.
    Interpretation and limitations
    Timing and serial trend matter; broad urine drug screens are neither sensitive nor specific enough to be a reference standard.
  6. 06
    Reference-standard toxicology decision support
    Why
    Integrate product, dose, time, clinical features and validated assays through current TOXBASE and NPIS guidance.
    Interpretation and limitations
    A negative generic screen cannot override a credible exposure; specialist interpretation is the UK decision standard in severe or complex poisoning.

Differential diagnosis

01

Sepsis or CNS infection

Fever, altered consciousness and shock can resemble poisoning, and a reported ingestion must not prevent cultures, antimicrobials or lumbar and imaging decisions when clinically indicated.

02

Metabolic or endocrine emergency

Hypoglycaemia, DKA, adrenal crisis, inborn metabolic disease and electrolyte disturbance can present with vomiting, coma, arrhythmia or unusual breathing.

03

Seizure or intracranial disease

Postictal state, trauma, haemorrhage and raised intracranial pressure remain possible, particularly when exposure history is uncertain.

04

Medication adverse effect at a therapeutic dose

Renal or hepatic dysfunction, interaction or pharmacogenetic susceptibility can produce toxicity despite apparently correct administration and needs medication reconciliation.

Management

01Unknown exposureStabilise and reconstructFirst stepA child has unexplained altered physiology or a possible ingestion without reliable details.+
  1. 1Use ABCDE, glucose, temperature and ECG and treat immediate threats.
  2. 2Gather packaging, scene and collateral history and calculate the maximum dose.
  3. 3Consult TOXBASE and send targeted rather than indiscriminate tests.
  4. 4Keep sepsis, trauma, metabolic and neurological disease in the differential.
02Recent known ingestionUse substance-specific riskProduct, dose and time can be estimated.+
  1. 1Calculate mg/kg from the maximum missing quantity and current weight.
  2. 2Check the specific TOXBASE monograph for observation, sampling and treatment.
  3. 3Consider charcoal only when the named criteria and airway safety are met.
  4. 4Do not discharge until the full agent-specific delayed-risk window is satisfied.
03ParacetamolTime the sample and antidoteA paracetamol overdose or therapeutic excess is possible.+
  1. 1For a known single acute ingestion obtain the level at four hours or later.
  2. 2Start acetylcysteine immediately for staggered or uncertain timing when indicated.
  3. 3Follow one locally approved NAC regimen with independent dose and bag checks.
  4. 4Review paracetamol, ALT, INR, renal function and acid-base criteria before stopping.
04Prevention and safetyClose the access routeThe child is medically stable after accidental, erroneous or intentional exposure.+
  1. 1Assess developmental access, supervision, storage and caregiver dose technique.
  2. 2Complete mental-health and suicide-risk assessment for intentional ingestion.
  3. 3Follow safeguarding procedures for unsuitable or repeated explanations or deliberate administration.
  4. 4Give a written medicine and household safety plan and arrange follow-up ownership.
Key medicines and prescribing safety1 treatment · regimens, roles and cautions+
Antidote for paracetamol overdose when the timed concentration or staggered, uncertain or delayed presentation meets the current UK treatment pathway.

Intravenous acetylcysteine

Under the authorised 21-hour regimen give 150 mg/kg IV over 1 hour, then 50 mg/kg over 4 hours, then 100 mg/kg over 16 hours, total 300 mg/kg; continue at the third-infusion rate when the clinical and laboratory stopping criteria are not met.

Use the current TOXBASE and local weight-based table, one complete regimen and an independent check. Monitor for anaphylactoid reaction and fluid volume in small children; previous reaction is not an absolute contraindication when treatment is required. Some services use an approved SNAP regimen only in defined eligible patients.

Complications

01

Respiratory and cardiac arrest

Central depression, airway loss, aspiration, sodium-channel blockade, severe electrolyte change or refractory shock can cause sudden arrest and may require prolonged resuscitation.

02

Delayed organ failure

Hepatic necrosis, acute kidney injury, rhabdomyolysis, pancreatitis and hypoxic brain injury can emerge after early symptoms settle.

03

Decontamination harm

Induced vomiting, unprotected activated charcoal, inappropriate gastric lavage or neutralising corrosives can cause aspiration, perforation, thermal reaction and treatment delay.

04

Recurrence and psychosocial harm

Unaddressed storage, caregiver dosing systems, neglect, exploitation or self-harm risk exposes the child and siblings to repeated poisoning.

Monitoring and follow-up

  • Use continuous oximetry and ECG for reduced consciousness, respiratory depression, cardiovascular toxicity or a high-risk product.
  • Repeat airway, pupil, neuromuscular, temperature and haemodynamic observations at the substance-specific frequency.
  • Track QRS and QTc trends after cardiotoxic exposure and correct potassium, magnesium, hypoxia and acidosis as advised.
  • Repeat glucose for sulfonylurea, insulin, alcohol and other hypoglycaemic risk even after an initial normal result.
  • During acetylcysteine monitor infusion, fluid volume and reaction, and check the required blood tests before the planned stop time.
  • Record TOXBASE monograph version or access time and the NPIS advice, including thresholds for repeat testing and discharge.
  • Before discharge document safe storage, caregiver dosing, mental-health plan, safeguarding outcome and who will follow the child.

Special situations

The maximum dose is the safe assumption

When the floor count is uncertain, calculate from the largest quantity that could be missing rather than the most comforting estimate.

A toxidrome is a direction

It selects urgent treatment and tests but mixed ingestion and medical mimics still need active consideration.

The clock can be diagnostic

Formulation and time determine when a level is useful, how long a well child is observed and when treatment must begin.

Charcoal has its own toxicity

Aspiration risk makes indiscriminate decontamination more dangerous than many low-risk ingestions.

Prevention includes the whole household

Sibling medicines, visiting relatives, handbags, nicotine products and caregiver concentration errors are common access routes to close.

Common pitfalls

  1. 01

    Reassuring from the number of tablets without checking strength, formulation, weight and worst-case quantity.

  2. 02

    Using a broad urine toxicology screen to exclude poisoning.

  3. 03

    Taking a paracetamol level before four hours and interpreting it on the nomogram.

  4. 04

    Using the nomogram for a staggered or uncertain-time ingestion.

  5. 05

    Inducing vomiting or giving activated charcoal without toxin-specific and airway assessment.

  6. 06

    Mixing the authorised and SNAP acetylcysteine regimens.

  7. 07

    Stopping observation because the child looks well before delayed toxicity is excluded.

  8. 08

    Treating intentional overdose as misbehaviour rather than a medical and mental-health emergency.

  9. 09

    Missing maltreatment when a non-mobile child could not independently access the substance.