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Hemolytic anemia after zopiclone overdose.
Hin Tat Jeffrey Fung1, Cing Hon Lai, Oi Fung Wong
1Accident & Emergency Department, Tuen Mun Hospital, Hong Kong, China. funght@ha.org.hk
Clinical Toxicology (Philadelphia, Pa.)
|October 14, 2009
Summary
Zopiclone overdose can cause oxidative hemolysis, a serious blood disorder. This case highlights the potential for severe hematological complications beyond methemoglobinemia following excessive zopiclone intake.
Area of Science:
- Toxicology
- Hematology
- Pharmacology
Background:
- Zopiclone, a non-benzodiazepine hypnotic, is known to be associated with methemoglobinemia.
- This report investigates a rare hematological complication arising from zopiclone overdose.
Observation:
- A case study involving a 46-year-old woman who ingested a large quantity of zopiclone (50-100 tablets of 7.5 mg).
- Clinical presentation included signs suggestive of oxidative hemolysis.
Findings:
- The patient exhibited anemia, characteristic 'bite cells' on peripheral blood smear, elevated unconjugated bilirubin, and increased lactate dehydrogenase.
- Laboratory results also showed decreased haptoglobin levels and reticulocytosis, confirming active hemolysis.
Implications:
- Zopiclone overdose may induce significant oxidative stress, leading to hemolysis.
- This finding expands the known spectrum of hematological toxicity associated with zopiclone, beyond methemoglobinemia.
- Clinicians should consider hemolysis in the differential diagnosis of hematological abnormalities in zopiclone overdose cases.
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