Please temporarily stop taking your metformin. It is not safe to take metformin when you are severely dehydrated or unable to eat, as this increases the risk of a rare but serious side effect. You should not self-prescribe the ofloxacin-ornidazole combination, as antibiotics can sometimes worsen diarrhea and may not be necessary. While ondansetron can help control vomiting, self-medicating while dehydrated requires caution. Because you have been unable to eat for two days, please consult a doctor immediately for safe, personalized treatment. In the meantime, try to sip on oral rehydration solutions to stay hydrated.