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Published on: November 19, 2014
Isoniazid-induced psychosis
1Department of Psychiatry, State University of New York Health Science Center, Syracuse, USA.
Objective:
To report a suspected case of isoniazid-induced psychosis in a 31-year-old woman.
Case Summary:
A 31-year-old white woman without a prior psychiatric history presented with psychotic symptoms suspected to be related to prophylactic treatment with isoniazid after she tested positive to a tuberculin (purified protein derivative) test. The psychotic symptoms resolved partially after isoniazid was discontinued and completely after treatment with olanzapine was begun. The patient remained symptom-free 11 months after discharge from the hospital.
Discussion:
Cases of isoniazid-related psychiatric disorders reported in the literature include psychosis, obsessive-compulsive neurosis, and mania. With the increasing prevalence of tuberculosis in the US, more people are expected to receive treatment for tuberculosis. Pyridoxine deficiency may play a role in the pathogenesis of isoniazid-induced psychosis. Such deficiency states may be detected indirectly by measuring urinary metabolites of tryptophan.
Conclusions:
Clinicians should be aware of this adverse effect of isoniazid and that it may present with a broad clinical picture.
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