Aspirin Overdose

Question 1

Define aspirin overdose.

Answer 1

Potentially fatal poisoning occurring as a result of ingestion or, rarely, topical exposure to salicylates. Can present acutely or indolently with more chronic exposure.

Question 2

Explain the aetiology/risk factors of aspirin overdose.

Answer 2

The most common source of salicylate poisoning is aspirin (acetylsalicylic acid), which is rapidly hydrolysed to salicylate in the gastrointestinal tract and bloodstream.

Question 3

Summarise the epidemiology of aspirin overdose.

Answer 3

In the UK, deaths by suicidal overdose of analgesics, including salicylates, were reduced by 22% in the year immediately after the introduction in 1998 of legislation limiting the pack size of analgesics that could be purchased.

Question 4

Recognise the presenting symptoms of aspirin overdose. Recognise the signs of aspirin overdose on physical examination.

Answer 4

Nausea, vomiting, haematemesis, epigastric pain
Fever and diaphoresis
Shortness of breath
Tachypnoea, hyperpnoea, Kussmaul’s respirations
Tinnitus and/or deafness
Malaise and/or dizziness
Movement disorders, asterixis, stupor
Confusion and/or delirium (irritability, hallucinations)
Coma and/or papilloedema
Seizures

Question 5

Identify appropriate investigations for aspirin overdose and interpret the results.

Answer 5

ABG
Serum electrolyte panel
Serum salicylate level
Serum urea and creatinine
Serum ketones
Blood glucose
FBC
Serum LFTs
Serum PT, activated PTT, INR
Toxicology screen
CXR
ECG