Abstract

Background: Quinacrine is an older antimalarial drug that remains in use for a variety of illnesses including treatment-resistant giardiasis.

Case Presentation: We report a patient with no prior psychiatric history who developed mild, prodromal psychiatric symptoms when treated with quinacrine for treatment-resistant giardiasis. Symptoms resolved when the drug was stopped, recurred with greater severity (requiring involuntary psychiatric hospitalization) when restarted and promptly resolved again when the drug was finally stopped.

Conclusion: Although quinacrine remains in use today, providers may be unaware of its potential for serious neuropsychiatric toxicity.

Keywords: Quinacrine, quinolines, psychosis, adverse drug reaction, case report, giardiasis.