Acute digoxin poisoning manifests with vomiting, hyperkalaemia and brady-tachyarrhythmias potentially leading to death, whereas chronic digoxin toxicity is far more insidious, still with gastrointestinal symptoms but in addition bradycardia and automaticity on the ECG.
Quinine causes cinchonism (nausea, vomiting and tinnitus) in overdose but also blindness which is delayed and sometimes not noticed until the morning after the acute toxicity has resolved. Think of it as aspirin (the salicylism) that causes blindness.
NSAIDs are generally benign in overdose unless a large amount is ingested which would take some effort. As 66% of NSAID overdoses are with ibuprofen we will use this as an example.
Hypoglycaemia can occur at therapeutic doses especially in those who develop renal impairment. In overdose these drugs cause a profound and prolonged hypoglycaemia, usually apparent within 8 hours post ingestion of a standard preparation.
Metformin rarely causes hypoglycaemia but it can cause a profound lactic acidosis in overdose and in patients with renal failure.
Salicylates in acute overdose classically cause a respiratory alkalosis by stimulating the respiratory centres in the brain followed by a metabolic acidosis by uncoupling oxidative phosphorylation. The classic triad of mild toxicity is nausea, vomiting and tinnitus,
Tramadol in overdose would have the opiate toxidrome expected (sedation and respiratory depression) but it also can potentially cause seizures in doses >1.5 grams. Tramadol has also been associated with serotonin toxicity, rarely as a single agent but commonly with other co-ingested serotinergically active agents.
While insulin overdose should be simple to manage this guide will show you some of the nuances to the management and help you prevent longterm neurological impairment.
Chloral hydrate is used in paediatrics undergoing procedures. It was withdrawn from the adult arena due to the narrow therapeutic index. In overdue it causes rapid CNS depression, cardiac dysrhythmias and these are lethal without prompt intervention.Chloral hydrate comes in 200ml bottles, 1g/10ml
Local Anaesthetic toxicity is nearly always due to a therapeutic error. Usually an incorrect dose, route or technique.
Potential or definite snakebite is a common presentation to Australian emergency departments.
The 12-lead ECG provides valuable real-time prognostic information that is based on toxic effects at the target organ; often not available from clinical evaluation or serum drug assays.