Poisoning and overdose are increasing public health concerns in the UK, with a significant number of cases resulting in hospital admissions and deaths. In England alone, poisoning accounted for over 115000 hospital attendances between 2021 and 2022, with drug poisoning responsible for 4907 deaths in 2022 (NHS England, 2022; Office for National Statistics, 2023). Nurses, as essential frontline healthcare workers, play a pivotal role in managing poisoning cases from emergency triage to patient discharge. Their responsibilities include recognising the signs of poisoning, initiating treatments and collaborating with other health professionals.
Acute poisoning occurs when a person absorbs a toxic substance that leads to harmful effects. Poisons may be pharmaceuticals, household chemicals, industrial compounds or natural toxins from plants or animals (Owais and Khan, 2015). Poisoning may occur via ingestion, injection, inhalation or dermal exposure. It is typically categorised as either accidental or deliberate, with distinct patterns in children and adults (Sandilands and Bateman, 2016).
This article explores the theoretical underpinnings, clinical interventions and ethical complexities involved in treating poisoning and overdose. It also examines the role of nurses and the importance of continuing professional development in responding to the changing landscape of toxicology.
Patterns of poisoning and overdose
Accidental poisoning occurs frequently in children, particularly in those aged <6 years, who may unknowingly ingest harmful substances while exploring their environment (BMJ Best Practice, 2024). Medications, household cleaning products and pesticides are common causes. Adults can also be accidentally poisoned, particularly through occupational exposure, natural toxins (eg snake venom) or mismanagement of medications. Conversely, many poisoning cases among adolescents and adults involve deliberate self-harm (Sandilands and Bateman, 2016; National Poisons Information Service (NPIS), 2024).
Overdose, particularly related to illicit drugs and alcohol, is of significant concern. It may occur accidentally, as with unintentional overdoses of prescription medications, or deliberately, as in cases of suicide attempts. The misuse of opioids, including synthetic opioids such as fentanyl, has led to an increasing number of overdoses globally, further complicating treatment protocols (Boyer, 2012).
The role of the National Poisons Information Service
The NPIS provides vital support for health professionals managing poisoning cases. Its online resource, TOXBASE (www.toxbase.org), has seen a significant increase in use since its launch in 1999, with enquiries rising by >60% by 2022 (NPIS, 2024). Because of issues around data collection, it is difficult to determine the precise frequency of poisoning, but there are clear links between the use of TOXBASE and emergency department admission (Pyper et al, 2020).
The most frequently researched substances on TOXBASE include paracetamol, ibuprofen and sertraline, which aligns with their prevalence in overdose cases (NPIS, 2024). Paracetamol, widely used as a painkiller, is easily accessible and inexpensive, making it a common choice in intentional overdoses (Park et al, 2015). Sertraline, an antidepressant, has also seen a surge in prescription use, contributing to its presence in overdose scenarios (Lalji et al, 2021). This highlights the importance of nurses being familiar with the pharmacology and toxicology of these commonly encountered substances.
Theoretical frameworks in poisoning and overdose management
Nursing practice in the treatment of poisoning and overdose is underpinned by several theoretical frameworks.
The biomedical model, which forms the foundation of acute care, focuses on the biological and chemical processes involved in poisoning and the medical interventions required to correct them (Fuller, 2017). This model emphasises immediate, targeted treatment to address the physiological effects of toxins, such as respiratory depression in opioid overdose or liver damage in paracetamol poisoning.
In addition to the biomedical approach, the social model of health plays a role in understanding the broader factors contributing to poisoning and overdose, especially in cases of substance misuse and intentional self-harm. This model considers the social, economic and psychological factors that may lead individuals to overdose (Jalali et al, 2020). For example, poverty, unemployment and mental health issues are significant risk factors for substance misuse, which in turn increases the risk of overdose.
Maslow's hierarchy of needs offers insight into the psychological factors behind intentional poisoning or overdose. According to Maslow (1943), individuals must meet basic physiological and safety needs before addressing higher-level psychological needs, such as self-esteem and self-actualisation. When these needs are unmet, individuals may engage in harmful behaviours, such as drug misuse or self-harm. Nurses must be attuned to these underlying psychological factors when assessing and treating patients who present with intentional overdoses.
Initial stabilisation and management of poisoning
When patients present with suspected poisoning or overdose, immediate stabilisation is critical. Nurses are often the first health professionals to encounter poisoned patients and must be skilled in rapid assessment and intervention. Initial management follows the ABCDE (airway, breathing, circulation, disability and exposure) approach (British National Formulary (BNF), 2025). This structured approach ensures that lifethreatening symptoms are identified and treated early.
One of the most important elements in the management of poisoning is the recognition of toxidromes—clusters of signs and symptoms that are characteristic of specific toxins (Gonzalez and Mackay, 2022). Recognising a toxidrome allows for the prompt identification of the toxic agent and the initiation of appropriate treatments. Table 1 outlines common toxidromes and the poisons typically associated with them.
| Toxidrome | Clinical features | Likely poison |
|---|---|---|
| Anticholinergic | Agitation, dry skin, mydriasis, tachycardia | Tricyclic antidepressants, antihistamines |
| Cholinergic | Miosis, salivation, bronchorrhoea, diarrhoea | Organophosphates, nerve agents |
| Opioid | Coma, miosis, reduced respiratory rate | Morphine, heroin |
| Sedative-hypnotic | Coma, hypotonia, hyporeflexia, hypotension | Barbiturates, benzodiazepines ethanol |
| Serotonin | Agitation, confusion, myoclonus, hyperreflexia | Selective serotonin reuptake inhibitors, ecstasy |
| Sympathomimetic | Agitation, convulsions, mydriasis, tachycardia | Amphetamines, cocaine, caffeine |
Symptom management and pharmacological interventions
In many cases, treatment focuses on managing symptoms rather than targeting the poison itself. For example, ensuring adequate ventilation is crucial in cases where respiratory function is compromised, as seen in opioid overdoses (BNF, 2025). Oxygen therapy is often employed in cases of inhaled toxins such as carbon monoxide or irritant gases (Smollin, 2024).
Another important aspect of poisoning management is preventing the absorption of the toxin into the bloodstream. Activated charcoal is frequently used for this purpose as it binds to toxins in the gastrointestinal tract and prevents their systemic absorption. It is most effective when administered within 1 hour of toxin ingestion (Silberman et al, 2023). Activated charcoal is effective against a wide range of substances, including paracetamol, aspirin and tricyclic antidepressants (Chiew and Buckley, 2021).
In addition, specific antidotes are available for certain poisons, such as acetylcysteine for paracetamol poisoning and naloxone for opioid overdose. These antidotes work by either neutralising the toxic agent or reversing its effects on the body.
Pharmacological interventions: antidotes
Acetylcysteine for paracetamol overdose
Paracetamol is one of the most common causes of overdose in the UK because of its wide availability and frequent use for pain relief. In cases of paracetamol poisoning, the antidote acetylcysteine is administered intravenously to prevent liver damage (BNF, 2025). It is most effective when given within 8 hours of ingestion (Chiew et al, 2021). However, delayed treatment can still benefit patients with signs of liver toxicity.
The acetylcysteine regimen involves three consecutive intravenous (IV) infusions, with frequent monitoring of liver function tests and coagulation parameters. One problem in administering acetylcysteine is its potential for adverse reactions, such as nausea, vomiting and anaphylactoid reactions. Nurses must monitor patients closely for these side effects and be prepared to manage them (BNF, 2025).
Naloxone for opioid overdose
Naloxone is a life-saving antidote used to reverse the effects of opioid overdose, particularly respiratory depression (Royal College of Emergency Medicine and National Poisons Information Service, 2024). It works by competitively binding to opioid receptors, displacing opioids such as morphine, heroin, and fentanyl. Naloxone can be administered via IV, intramuscular, or intranasal routes, with IV being the preferred method in acute settings.
Because of the increasing prevalence of synthetic opioids, such as fentanyl, which are more potent and longer lasting than traditional opioids, higher or repeated doses of naloxone may be required (Boyer, 2012). Nurses must be prepared to administer multiple doses and continuously monitor patients for recurring symptoms, as naloxone's half-life is shorter than that of most opioids.
Flumazenil for benzodiazepine overdose
Flumazenil is the antidote for benzodiazepine overdose, reversing sedation and respiratory depression by competing with benzodiazepines for binding at the gamma aminobutyric acid type A receptor (Sivilotti, 2016).
However, its use is controversial as it carries a the risk of precipitating seizures, especially in patients with a history of long-term benzodiazepine use or mixed overdoses involving tricyclic antidepressants (Sharbaf Shoar et al, 2024). Flumazenil should be administered only in controlled settings, and nurses must be vigilant in monitoring for adverse effects.
Multidisciplinary approach
Nurses play a critical role within a multidisciplinary team when managing poisoning and overdose cases. This team may include emergency physicians, clinical toxicologists, intensivists, mental health professionals and social workers. Collaboration across disciplines is essential for providing comprehensive care that addresses both the physiological and psychological needs of the patient (Fok et al, 2016).
Ethical issues
Poisoning, particularly in cases of intentional overdose, raises several ethical challenges. Patient autonomy is a fundamental principle in healthcare, but it becomes complex when dealing with individuals who have deliberately ingested toxic substances to harm themselves. Nurses must balance respect for patient autonomy with the principle of beneficence – the obligation to act in the patient's best interest.
In cases of severe overdose, patients may lack the capacity to make informed decisions about their treatment. Nurses must then rely on legal and ethical frameworks to guide care, considering factors such as advance directives, family input and the potential for recovery (National Institute of Health and Care Excellence (NICE), 2024). Additionally, the involvement of mental health professionals is crucial in these cases to assess the patient's mental state and provide appropriate psychiatric care.
Psychosocial evaluation and aftercare
Once the patient is stabilised, a psychosocial evaluation is necessary to assess the underlying causes of the poisoning or overdose and to plan for ongoing care. This evaluation should include an assessment of the patient's mental health, social circumstances and support systems (NICE, 2024). The goal is not only to treat the acute poisoning but also to prevent future incidents by addressing the root causes.
For individuals who have experienced a deliberate overdose, referral to mental health services is essential. Cognitive behavioural therapy and other therapeutic interventions can help patients develop healthier coping mechanisms and reduce the risk of future self-harm (Beck, 2020). Nurses play a key role in facilitating these referrals and ensuring patients receive the support they need.
Additionally, in cases of substance misuse, patients may benefit from participation in drug and alcohol rehabilitation programmes. The provision of take-home naloxone kits for individuals at risk of opioid overdose is an effective harm-reduction strategy that has been shown to reduce mortality (Department of Health and Social Care, 2019). Nurses should educate patients and their families on the use of naloxone and the importance of seeking prompt medical attention in the event of an overdose.
Conclusion
Poisoning and overdose are complex medical emergencies that require prompt, effective treatment by health professionals. Nurses are central to the management of these cases from the initial assessment and stabilisation of the patient to the administration of antidotes and ongoing psychosocial support.
By understanding the pharmacology and toxicology of commonly encountered substances, recognising toxidromes and collaborating within a multidisciplinary team, nurses can provide high-quality, evidence-based care to patients with poisoning or overdose. However, the challenges in managing these cases extend beyond the physical symptoms. Ethical dilemmas, such as balancing patient autonomy with the need for life-saving interventions, are common in cases of intentional overdose. Nurses must approach these situations with compassion, ensuring that patients receive both medical and emotional support. Ultimately, a holistic approach that integrates both acute medical care and long-term psychosocial interventions is essential for preventing future episodes of poisoning or overdose. By embracing this comprehensive model of care, nurses can help patients achieve better outcomes and reduce the incidence of poisoning-related morbidity and mortality.