Side-effects of quinolones: comparisons between quinolones and other antibiotics.

Fluoroquinolones are generally very safe antibiotics which do not cause serious or life-threatening adverse reactions. The most frequent side-effects are gastrointestinal reactions (nausea, dyspepsia, vomiting) and CNS reactions such as dizziness, insomnia and headache. Many of the more severe CNS reactions seem to be due to metabolic interaction with theophylline, especially when enoxacin is used. Of the potentially serious side-effects, photoxicity has been reported in varying frequencies with the different fluoroquinolones. Caution is necessary when this group of drugs, especially pefloxacin, is prescribed to patients who will have intensive exposure to UV light during treatment. The finding in juvenile animals of cartilage damage after administration of high doses have resulted in recommendations that fluoroquinolones should not be used in children. Carefully monitored studies should be performed in paediatric patients to assess whether there is a real risk of such adverse reactions.