An Interesting Case of Ingestion by Dr. Loran Hatch
Fri, 08/31/2018 - 9:10pm
Plaquenil (Hydroxychloroquine) Overdose
- Small toxic to therapeutic window, 5g can lead to severe poisoning in adults
- Clinical sx: abdominal pain, N/V/D, hypotension, apnea, dizziness, headache, convulsions
- Cardiotoxicity:
- Sodium channel blockade - QRS widening
- Potassium channel blockade - QT prolongation
- Can also see AV block, ST and T wave depression
- Hypokalemia - due to intracellular shift - indicator of severity of overdose
- Management: Aggressive supportive care
- Consider early intubated and early activated charcoal
- Fluid resuscitation
- Epinephrine is the vasopressor of choice -Rec: 0.25 µg/kg/min increasing by 0.25 µg/kg/min until SBP > 90 mmHg
- Diazepam - augments tx of dysrthythmias and hypotension
- Also tx of seizures and for sedation
- Sodium bicarb to correct wide QRS (goal 100ms) / Note can exacerbate hypokalemia
- Permissive hypokalemia (consider repleting in severe hypokalemia).
Barry J. Antimalarials. In: Hoffman RS, Howland M, Lewin NA, Nelson LS, Goldfrank LR. eds.Goldfrank's Toxicologic Emergencies, 10e New York, NY: McGraw-Hill; 2015