My dad took fluconazole and ciprofloxacin together and he woke up in the middle of the night vomiting and fainted and fell on the floor without conscious. woke up and feels very sick. going to er. what could that be?

Dehydration or other: Fluconazole and ciprofloxacin can cause irregular heart rhythms, possibly due to a conduction abnormality termed QT prolongation. In addition, vomiting and diarrhea can cause dehydration and resultant low blood pressure which can cause fainting. An EKG can determine the cardiac effects. A careful physical exam can search for other causes of fainting.