Adverse reactions to fluoroquinolones in the Nigerian population: an audit of reports submitted to the National Pharmacovigilance Centre from 2004 to 2016

Adverse drug reactions (ADRs) recorded in national pharmacovigilance databases in developed countries have been analyzed. However, adverse reactions to fluoroquinolones were observed globally despite their wide use and safety concerns. We provided information on the pattern of adverse reactions to fluoroquinolones reported spontaneously to the National Pharmacovigilance Centre (NPC), Nigeria. ADRs to fluoroquinolones reported to the NPC, over a period of 12 years, were analyzed. Evaluation was done for annual reports, age and gender of patients, type of reporter, suspected fluoroquinolones and adverse reactions, onset and outcome of ADRs, and causality. A total of 18527 ADR reports were received by the NPC. Antibiotics accounted for 1371(7.4%) of the total reports and fluoroquinolones accounted for 256 (18.7%) cases. A total of 540 ADRs due to fluoroquinolones was experienced by the patients. Multiple ADRs were experienced by 165 (65%) patients. Norfloxacin (2; 0.8%), moxifloxacin (3; 1.2%), ofloxacin (10; 3.9%), ciprofloxacin (112; 43.8%), and levofloxacin (129; 50.4%) were responsible for the ADRs. Neurological disorders (121; 22.4%), gastrointestinal disorders (118; 21.9%), and skin-appendage disorders (116; 21.5%) were the most reported ADRs, while pruritus (41; 7.6%), abdominal pain (34; 6.3%), vomiting (34; 6.3%), and skin rash (27; 5.0%) were the most frequently reported specific ADRs. Thirty-four (6.4%) patients experienced serious ADRs. Fluoroquinolones accounted for a small but significant proportion of ADRs spontaneously reported to the NPC in Nigeria. Ciprofloxacin and levofloxacin were the two most culpable fluoroquinolones due to their inappropriate use or increased use in multi-drug resistant tuberculosis (MDR-TB) treatment.