 In treated patients the most common adverse reactions are gastrointestinal, including dyspepsia, nausea, vomiting, flatulence, abdominal pain, diarrhea and sometimes constipation.Also common disorders affecting the skin (itching, urticaria, rash, phototoxicity and photosensitivity) and central nervous system (dizziness, headache, tremor, paresthesia, impaired sense of taste and smell), psychiatric disorders (alteration of the sleep-wake cycle state of anxiety, depression, hallucinations and nightmares).Fleroxacin and other fluoroquinolones, are known to trigger seizures or lower the seizure threshold, due to their inhibitory activity on GABA receptor binding.