II. Mechanism
- Quinine is a Class Ia Antiarrhythmic Drug
-
Quinine in Overdose blocks cardiac Sodium channels
- Decreased cardiac inotropy
- Decreased cardiac conduction velocity
-
Quinine in Overdose blocks cardiac Potassium channels
- Repolarization is prolonged
- Other Quinine effects in Overdose
- Anticholinergic Toxicity
- Increased Insulin release
- Ototoxicity
- Ophthalmic toxicity
- Vasodilation
III. Pharmacokinetics
- See Quinine
- Severe toxicity is associated with ingestions >1.5 to 8 grams
IV. Adverse Effects: Toxicity
- Cinchonism (reversible Quinine Toxicity)
- Severe Quinine Toxicity
- Cardiac
- Dysrhythmias
- EKG Abnormalities (e.g. Prolonged QTc, QRS Complex or PR Segment)
- Hypotension
- Miscellaneous
- Retinal ischemia (Retinal edema, Decreased Visual Acuity)
- Hypokalemia
- Hypoglycemia
- Cardiac
V. Labs
VI. Management
- Multidose Activated CharcoalDecontamination
- Start Activated Charcoal 1 g/kg
- Continue with 0.5 g/kg every 6 hours for 24 hours
-
Hypoglycemia
- See Hypoglycemia Management
- Intravenous Dextrose
- Consider Octreotide 50 mcg SQ every 6 hours
-
Wide QRS (>100 ms) with Hypotension
- Sodium Bicarbonate boluses until QRS narrows, hemodynamic stability
- Concurrently manage Hypokalemia (worsens with Sodium Bicarbonate)
-
Prolonged QTc with Torsades de Pointes
- See Torsades de Pointes
- ABC Management
- Defibrillation, overdrive pacing
- Magnesium Sulfate IV
- Disposition
- Admit symptomatic patients
- May discharge asymptomatic patients after 6-12 hours
VII. Resources
- Quinine Toxicity (Life in the Fast Lane)
VIII. References
- Carroll and Yakey (2024) Crit Dec Emerg Med 38(12): 32
- Langford (2003) Br J Clin Pharmacol 56(5):576-8 +PMID: 14651733 [PubMed]