Neuropsychiatric Quinism: Chronic Encephalopathy Caused by Poisoning by Mefloquine and Related Quinoline Drugs



Quinolines are neurotoxic drugs that have been widely used in malaria treatment and prevention, particularly in military settings. Poisoning by quinoline drugs, including by the previously commonly used drugs quinacrine, chloroquine, and mefloquine, can cause a lasting disorder named neuropsychiatric quinism, resulting from chronic encephalopathy and associated brain and brainstem dysfunction. Neuropsychiatric quinism is characterized by chronic symptoms that may mimic several psychiatric and neurologic disorders, including posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI). Neuropsychiatric quinism may have been widely unrecognized in veteran populations, and its symptoms misattributed to other causes, including cerebral malaria. Diagnosis of neuropsychiatric quinism is primarily clinical, and management of the disorder is primarily conservative. The unrecognized effects of neuropsychiatric quinism in veteran populations are likely to have confounded a significant body of military research and clinical diagnosis. These effects suggest the need to screen veterans for a past history of symptomatic exposure to quinolines, and to approach the development of new quinoline drugs for military use with caution.


Quinacrine Chloroquine Primaquine Mefloquine Tafenoquine PTSD TBI Malaria 


Conflict of Interest Statement

Dr. Nevin serves as consultant and expert witness in legal cases involving claims of adverse effects from antimalarial drugs.


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Authors and Affiliations

  1. 1.The Quinism FoundationWhite River JunctionUSA

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