#EMConf: Tox in the news
What we know about chloroquine overdose comes from experience in France (suicide cases) and areas of malaria.
Death can occur within 1 hour of toxic ingestion!
Hydroxychloroquine was derived from chloroquine in 1946 – less toxic
Used in malaria treatment and prophylaxis (blocks erythrocyte destruction)
Used in treatment of rheumatoid arthritis, lupus, etc (anti-inflammatory)
Clinical symptoms: N/V/D, drowsy, AMS, seizure
HYPOTENSION, usually within 1 hour of toxic ingestion
Blocks Na channels – prolongs QRS
Blocks K channels – prolongs QTc, risk of Torsades
Hypokalemia (from intracellular shifting)
TREATMENT of hydroxychloroquine overdose extrapolated from treatment of chloroquine overdose – aggressive, early supportive care
*Consider activated charcoal via NG tube (consider w/in 2 hours of ingestion)
*Benzo of choice = Diazepam (high doses)
2mg/kg over 30 minutes
Some animal studies and case reports of co-ingestion of diazepam and chloroquine found benefit - better hemodynamic stability
*Vasopressor of choice = Epinephrine
0.25mcg/kg/min titrated for SBP >90
*Permissive hypokalemia (~2.5 mmol/L)
Can lead to rebound hyperkalemia and dysrhythmias as poisoning resolves if potassium is overly corrected
Note - Epi and Na bicarb can worse hypokalemia
Need to Watch electrolytes closely!
*Na Bicarb to counter Na blockade effects (if QRS >110 ms)
*Intralipid emulsion therapy
Case reports that show it may help – early treatment led to survival
Creates a lipid sink to grab onto free circulating drugs and maybe pulls drug off receptors, also thought to improve cardiac contractility
Little down side – can interfere with some lab results and ECMO circuits
Right now there is not great data on hydroxychloroquine/chloroquine in the treatment of COVID-19.
The Cooper EM team plans to discuss the article on hydroxychloroquine and azithromycin in treatment of COVID-19 at our journal club today! Stay tuned!