Bodily entry of toxic substances in amounts that cause dysfunction of body systems.


  • Microorganisms (food poisoning)
  • Fluids and gases (organic), e.g., agricultural chemicals, petrol, paraffin, carbon monoxide
  • Metal poisoning (inorganic), e.g., lead, mercury, copper
  • Alcohol, drugs of abuse, medicines (in excessive amounts)

Acute poisoning can occur by ingestion, inhalation, injection or cutaneous/mucosal absorption.

Exposure can be intentional (e.g., suicide or homicide attempt), unintentional (e.g., medication error) or environmental/ occupational.

Principles of general management

  • If possible, refer patients showing signs of poisoning to hospital for admission. Send a note of what is known about the poison and what treatment has been given
  • Also refer/admit patients who have taken slow-acting poisons even if they appear well. These include: acetylsalicylic acid, iron, paracetamol, tricyclic
    antidepressants (e.g., amitriptyline, imipramine), paraquat, modified-release products
  • Optimal management of the poisoned patient depends upon the specific poison(s) involved, the presenting and predicted severity of illness and time that has elapsed between exposure and presentation
  • Treatment includes supportive care, decontamination, antidotal therapy and enhanced elimination techniques
  • It may not always be possible to identify the poison and the amount taken. Anyway,
    • Only a few poisons have specific antidotes
    • Few patients need active removal of the poison
    • Most patients must be treated symptomatically

However, knowledge of the poison will help you anticipate the likely effects on the patient.