Adverse drug reactions to fluoroquinolone antibiotics - Analysis of reports received in a tertiary care hospital

Fluoroquinolones are one among the most commonly prescribed antibiotics in hospital set up. Only few published studies are available which tried to characterize the nature of ADRs to fluoroquinolones encountered in a hospital set up. The present study was aimed at analyzing the pattern of ADRs implicated to fluoroquinolone antibiotics reported spontaneously to the ADR reporting unit of a tertiary care teaching hospital in India. ADRs reported over a period of 4 years and 6 months were analyzed. Evaluation was done for patient demographics, drug and reaction characteristics, predisposing factors, and outcome of reactions. Analysis for causality, severity and preventability was also done. Eighty ADRs associated with fluoroquinolones were notified during the evaluation period, which accounted for 5.4% of the total ADRs reported in the ADR reporting unit and 30.2% of all reports to antibacterials. Type A reactions (58.8%) accounted for majority and more were described to be common (48.8%) in the literature. Levofloxacin (48.8%) occupied the major share of the reactions reported. Pattern of ADRs observed was comparable to that reported in literature. The organ system most commonly affected was skin and appendages (32.5%) and the most frequently reported reaction was skin rash (21.3%). Interestingly, no report of reactions affecting musculoskeletal system was observed while rare reaction like nephrotoxicity was noticed. The proportion of nervous system adverse reactions noticed were higher than that observed with antibacterial agents in general. Drug dechallenge was instituted in majority (73.8%) for management of the reactions, while additional treatment was instituted in 50% of the reactions. More of the reactions were probable (52.5%) in nature on causality assessment and were of moderate (72.5%) severity. Many (23.8%) of the reactions were deemed to be preventable on evaluation. Drug-drug and drug-disease interaction were the most important factors which contributed to preventability. Even though ADRs to fluoroquinolones are considered mainly to be mild in severity, our evaluation revealed considerable number of reactions of moderate severity. The present evaluation has revealed opportunities for interventions especially for the preventable ADRs which will help in promoting safer use of this important group of antibiotics. Cautious use of these agents especially in patients with predisposing factors and proper monitoring is warranted. Spontaneous reporting programs in spite of its limitations are useful in identifying pattern of ADRs in a hospital set up. Similar hospital based evaluation will provide valuable information which would help in promoting safe use of these medications. © 2008 - IOS Press and the authors. All rights reserved.