Safe Prescribing — Flashcards

Flashcard 121: A _____ may be used in paracetamol overdose to determine if treatment is indicated

Answer: nomogram

Flashcard 122: Patients who have taken a paracetamol overdose should have a(n) _____ taken at 4 hours post-ingestion and 2 hours before completion of N-acetylcysteine

Answer: paracetamol level

Flashcard 123: Antidote for _____ overdose (especially if presenting >8 hours after ingestion):\nN-acetylcysteine (NAC)

Answer: paracetamol

Extra: In paracetamol overdose, NAC is most effective when given within 8 hours of ingestion. Serum paracetamol levels should be measured at 4 hours post-ingestion to determine the need for NAC using a nomogram.

Flashcard 124: Patients are at an increased risk of developing hepatotoxicity following a paracetamol overdose if they are taking _____ medications

Answer: liver enzyme-inducing

Flashcard 125: Liver transplantation is indicated for paracetamol overdose if arterial pH is _____ after fluid resuscitation.

Answer: <7.3

Extra: King's College Criteria for Paracetamol Overdose: Arterial pH < 7.3 (after fluid resuscitation) OR all three of: 1. Grade III or IV encephalopathy 2. Prothrombin time > 100 seconds (INR > 6.5) 3. Serum creatinine > 3.4 mg/dL (300 μmol/L)

Flashcard 126: Management of paracetamol overdose <1 hr after ingestion: _____ (consider NAC based on serum levels)

Answer: Activated charcoal

Extra: - Within 1 hour: Activated charcoal may be given.\n- After 4 hours: Paracetamol level should be measured to determine need for NAC using the Rumack-Matthew nomogram.\n- NAC is indicated immediately if ingestion was >8 hours ago and is potentially toxic (>150mg/kg), or if there is staggered ingestion/unknown time.