Ampicillin-sulbactam dosing

A 41-year-old woman, with liver lacerations, rib fractures, and pneumothorax after a motor vehicle accident, was given haloperidol for agitation on day 7. During the first 24 hours she received a cumulative intravenous dose of 15 mg, 70 mg on day 2, 190 mg on day 3,160 mg on days 4 and 5, and 320 mg on day 6. An hour after the first dose of 80 mg on day 7, she had ventricular extra beats followed by 5-beat and 22-beat runs of ventricular tachycardia. The rhythm strips were consistent with polymorphous ventricular tachycardia or torsade de pointes and the QTC interval was 610 ms (normally under 450 in women). She received intravenous magnesium sulfate 2 g. Concurrent medications included enoxaparin, famotidine, magnesium hydroxide, ampicillin/sulbactam, nystatin suspension, midazolam, and 0.45% saline with 20 mmol/1 of potassium chloride. She had no further dysrhythmias after haloperidol was withdrawn. Eight days after the episode of torsade de pointes she had a QTC interval of 426 ms. 

Children 1 year of age or older (less than 40 kg) 300 mg/kg/day IV (200 mg ampicillin/100 mg sulbactam) in divided doses every 6 hours. 

A woman immediately developed hyperpyrexia up to 40 C after a first dose of intravenous ampicillin-I-sulbactam, having previously tolerated ampiciUin alone for 10 days. Hyperpjrexia was repeatedly observed after six more doses of sulbactam (56). 

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