To the editor: This letter presents a case of clarithromycin-induced mania.
Ms. A, a 52-year-old woman with a history of three depressive episodes, was admitted for hyperenergetic, loud, and unfocused behavior. She was also elated and delusional. Two days earlier, she had been prescribed a regimen of clarithromycin, 500 mg b.i.d., and prednisone, 60 mg q.i.d., followed by a taper, for severe sinusitis. Results of a neurologic examination were within normal limits; laboratory data were also within normal range. The results of a drug-of-abuse screen were negative; Ms. A’s blood alcohol concentration was zero. Her clarithromycin was discontinued; the prednisone taper continued. Within 1 week, Ms. A responded to haloperidol and lithium treatment. She was tentatively diagnosed as having steroid-induced psychosis. Lithium was discontinued after 4 months because of the appearance of hypothyroidism, probably induced by lithium. Two years later, again 2 days after starting treatment with clarithromycin for an acute episode of sinusitis, Ms. A became agitated and acutely delusional. She believed she was "Jesus Christ," a singer and a superstar. She would scream intermittently. She had an expansive mood, flight of ideas, an intense affect, and looseness of associations, but no hallucinations. Her physical examination and laboratory results were unremarkable. Clarithromycin was discontinued, and Ms. A was started on a regimen of haloperidol and lithium. An unequivocal improvement was noted the next day with mildly pressured speech and an expansive mood, but a denial of delusions. Ms. A was discharged 6 days after her admission.
Ms. A had two similar episodes with clear evidence of mania and psychosis. During the first episode, she was taking both clarithromycin and prednisone; the mania and psychosis were thought to be due to the prednisone. Before the second episode, Ms. A was taking clarithromycin alone. We think that Ms. A’s case represents clarithromycin-induced mania. Her dose of clarithromycin in both episodes was 500 mg b.i.d. as opposed to the relatively high doses (1000 mg b.i.d.) described in the treatment of disseminated Mycobacterium avium-complex infections in two AIDS patients who developed manic episodes R4015511CHDBIJEH, similar to the results reported by Cone et al. R4015511CHDDEECA. Clarithromycin has excellent CSF penetration R4015511CHDDCEGH, but no reports of possible interaction with central neurotransmitters were found in the literature, although such interaction is a plausible assumption. There have been several reports of CNS side effects of clarithromycin: dizziness, lightheadedness, confusion, and insomnia R4015511CHDBFCCC, as well as visual hallucinations R4015511CHDDEJEC.