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Updated: May 27, 2026
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Assessment of Cocaine-induced Behavioral Sensitization and Conditioned Place Preference in Mice
Published on: February 18, 2016
Levamisole exposure and hematologic indices in cocaine users
Peter R Chai1, William Bastan, Jason Machan
1Division of Medical Toxicology, Department of Emergency Medicine, Alpert Medical School/Brown University, Providence, RI, USA.
Summary
Cocaine adulterated with levamisole (an antihelminthic) does not significantly alter hematologic indices in users. However, levamisole-associated neutropenia can present with oropharyngeal complaints or infections.
Area of Science:
- Toxicology
- Hematology
- Pharmacology
Background:
- Levamisole is a common adulterant in illicit cocaine.
- Levamisole exposure has been anecdotally linked to severe neutropenia and agranulocytosis.
- The hematologic effects of levamisole in cocaine users require further investigation.
Purpose of the Study:
- To compare hematologic indices in cocaine users with and without confirmed levamisole exposure.
- To assess the association between levamisole and neutropenia in a cocaine-using population.
- To identify clinical signs suggestive of levamisole toxicity.
Main Methods:
- Retrospective review of 95 cocaine-positive patients with complete blood counts.
- Categorization into levamisole-positive (n=47) and levamisole-negative (n=48) groups.
- Comparison of white blood cell count, absolute neutrophil count, and absolute lymphocyte count.
Main Results:
- No significant differences in total white blood cell count, absolute neutrophil count, or absolute lymphocyte count between groups.
- Incidence of neutropenia was 4.2% overall and 2.1% in the levamisole-positive group.
- Literature review revealed oropharyngeal complaints (52%) and infections/purpura (27%) in levamisole-induced agranulocytosis cases.
Conclusions:
- Levamisole adulteration in cocaine did not significantly impact overall hematologic indices in this cohort.
- Levamisole-associated neutropenia may present with specific clinical features like oropharyngeal issues or fever.
- A clinical algorithm for emergency department identification of levamisole toxicity is proposed.
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