Quick Review: Chloroquine and Hydroxychloroquine Toxicity

Toxic Dose

• Chloroquine: >5 g is associated with severe toxicity (though toxicity can occur at lower doses).
• Hydroxychloroquine (HCQ): Toxic dose is less well-defined.

Clinical Effects

• Seizures: Due to sodium channel blockade.
• Arrhythmias: Resulting from sodium channel blockade.
• Hypotension: Caused by alpha-adrenergic blockade.
• Hypokalemia: Often a notable feature.

Management

1. Decontamination:

• Administer activated charcoal if the patient is awake, alert, and has no risk of emesis.

1. Supportive Care:

• High-dose epinephrine:
• Recommended dose: 0.25 mcg/kg/min.
• Based on retrospective case-control series: https://www.nejm.org/doi/full/10.1056/NEJM198801073180101
• Diazepam:
• Administer 1–2 mg/kg over 30 minutes, followed by 1–2 mg/kg over 24 hours.
• Prevents seizures and may provide cardioprotective effects.

1. Airway Management:

• Consider early intubation to secure the airway in deteriorating cases.

1. Expert Consultation:

• Contact a poison center for guidance: 1-800-222-1222.

Support the show

• Tox Trinkets (Rep the show at home!)
• Support Toxo's repairs
• Review the show ON YOUR APP

Reach the show

• Email: Toxtalk1@gmail.com

More Show Resources

• Get Messages from Toxo (Newsletter)
• Ryan's Medical Games and Resources
• Show Website