Thanks for your query.
Oh, this is going to be a very big problem.
The reason being, Metronidazole by virtue of its antabuse effect will cause lots of problems. The vomiting may not stop and your friend can go into dehydration and related problems.
You have to rush her to the ER, tell the truth, get her admitted and treated accordingly.
Do not take any risk at home as matters can turn to worst.
I hope this answer helps you to understand the gravity of the situation and rush to ER.
These Q&A’s are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.