Can antibiotics cause a psychosis?: Case report and review of the literature

It is relatively unknown that some of the possible side effects of antibiotic treatment can be transient psychotic episodes and other encephalopathies such as seizure disorders. Since these are rare events, there have not been many studies about them, nor is there a clear understanding of the underlying basis for these symptoms. This phenomenon was recently brought to our attention by a patient whose case history is discussed here. For the past few years, he has been diagnosed at different times with schizophrenia, schizoaffective disorder, bipolar disorder with psychosis, temporal lobe epilepsy, and psychogenic nonepileptic seizures. He was seen by a neurologist and placed on carbamazepine, which by his admittance helped him tremendously. During this same time period, psychiatrists placed him on various antipsychotic medications as well. The patient researched many medical conditions and came to the conclusion that his symptoms are caused by a large dose of an "antibiotic" given to him on his first day of basic training for the military, the so called "peanut butter shot", although he has not been able to convince his physicians of this theory. Whether or not this patient has a chronic schizophrenia-like illness or an adverse reaction to antibiotics, this case is presented so that clinicians are aware that neurological and psychiatric side effects can occur as rare reactions to antibiotic therapy and that treatment with an anti-seizure drug concurrently used as a mood stabilizer may be warranted in such cases. Published by Elsevier B.V.