II. Mechanism
- See Colchicine
III. Pharmacokinetics
- See Colchicine
- Toxicity occurs with single or multiple excessive oral doses (narrow Therapeutic Index)
- Risk of progression to multisystem organ failure and death within days of Overdose
- Toxic Dose: 0.5 mg/kg
- Lethal Dose: 0.8 mg/kg
- Toxicity occurs in 3 phases
- Phase 1: Onset 10 to 24 hours after ingestion
- Gastroenteritis-like symptoms (if oral ingestion, may be absent with IV dosing)
- Phase 2: Onset 1 to 7 days after ingestion
- Multisystem organ dysfunction with risk of Sepsis and death
- Phase 3: Recovery within a few weeks of ingestion
- Recovery is typically complete except for complications from acute illness
- Phase 1: Onset 10 to 24 hours after ingestion
IV. Findings
- Gastrointestinal
- Cardiac
- Respiratory
- Renal
- Prerenal Azotemia
- Acute Kidney Injury
- Hematologic
- Neurologic
- Altered Level of Consciousness or confusion
- Neuropathy (late effect)
V. Labs
- See Unknown Ingestion for complete toxicologic workup (e.g. Serum Glucose, Acetaminophen level)
- Complete Blood Count
- Comprehensive metabolic panel
- Lactic Acid
VI. Diagnostics: Symptomatic Patients
VII. Management
- Consult poison control
- Various experimental protocols have been explored to aid Colchicine clearance and supportive care
- Examples: Exchange transfusion, Anticolchicine antibodies, Colony Stimulating Factors
-
Activated Charcoal
- Indicated for ingestion within prior 1 to 2 hours and no contraindications (e.g. aspiration risk)
- Multi-dose acivated charcoal may be indicated (consult poison control)
- Hypotension
- Anuric Acute Renal Failure
- Disposition
- Admit all symptomatic cases
- Asymptomatic cases of significant Overdose should be observed for at least 6 to 8 hours
VIII. Prognosis
- Poor prognostic factors include delayed presentation, pre-existing renal or liver dysfunction
IX. References
- Tomaszewski (2023) Crit Dec Emerg Med 37(11): 32
- Finkelstein (2010) Clin Toxicol 48(5):407-14 +PMID: 20586571 [PubMed]