Only limited data on overdose are available. Single doses of up to 1200 mg and multiple doses of 600 mg over 10 days were administered to healthy subjects without any significant undesirable effects. In the event of overdosage, it is recommended that appropriate supportive care including ECG measurements should be instituted as dictated by patient's clinical status.

After intravenous drug administration carbo medicinalis only slightly reduces systemic exposure (approximately 20%).

The use of oral charcoal early after oral administration may be useful to prevent excessive increase of systemic exposure to Avelox in cases of overdosage. Concomitant dosing of charcoal and 400 mg oral Avelox reduced the systemic availability of the drug by more than 80% by preventing absorption in vivo.