Three Cases of Myoclonus Secondary to Ciprofloxacin: "Ciproclonus"

OBJECTIVES: Ciprofloxacin is a fluoroquinolone that is used for bacterial infections involving different systems. In some cases, ciprofloxacin was reported to induce myoclonus. METHODS: We performed a chart review of 3 patients with myoclonus secondary to ciprofloxacin and reviewed the literature for similar cases. Written consent for publication was obtained from each patient, and their identities were concealed for ethical reasons. RESULTS: We describe 3 cases of myoclonus secondary to ciprofloxacin, 2 males and a female aged 61, 26, and 48 years, respectively. The myoclonus appeared within 3 days of ciprofloxacin intake. In all 3 cases, ciprofloxacin was prescribed for urinary tract infection. Electroencephalogram and neuroimaging studies were normal and possible causes were excluded. Thus, ciprofloxacin was believed to be the underlying cause and hence it was withdrawn. The patients had complete recovery on follow-up. CONCLUSIONS: Although ciprofloxacin is widely prescribed for different infections, only 13 cases were reported to develop myoclonus secondary to ciprofloxacin. The mean age of patients was 62 years. Fifty-four percent of cases were males. Cessation of ciprofloxacin was the most common management course. All individuals fully recovered after ciprofloxacin withdrawal. The mechanism of ciprofloxacin-induced myoclonus is probably associated with γ-aminobutyric acid and glutamate pathways.