Overdose and antidotes

Question 1

Early and late features of paracetamol OD?

Answer 1

Early (0-48) is often asymptomatic, or non-specific nausea/vomiting and abdominal pain.
Delayed (>48) get hepatic necrosis

Question 2

Clinical features of benzodiazepine overdose?

Answer 2

Nystagmua, ataxia, aggression, resp. depression, reduced GCS

Question 3

Contraindications to flumazenil in benzo OD?

Answer 3

Long term benzodiazepine use (precipitate withdrawal), concurrent substance ingestion which reduces seizure threshold, unknown substance overdose, seizure history, tachycardia, broad QRS. Therefore <10% of patients eligible.

Question 4

Features of TCA overdose?

Answer 4

1. Anticholinergic (dry mouth, dilated pupils, urinary retention, tachycardia, hyper-reflexia, hyper-tonia, seizures and coma)
2. Sodium channel blockage (key toxicity mechanism; get

Question 5

Features of SSRI overdose?

Answer 5

Common is nausea, vomiting, agitation, tremor, nystagmus, drowsiness, tachycardia;
15% get serotonin syndrome (clonus, tremor, hyperreflexia, ANS instability (may be hypertensive), tachycardic

Question 6

What are post-parvolex (NAC) bloods?

Answer 6

Looking for liver failure so do U&E, pH, coagulation, lactate, glucose.