First of all, if this lasts more than a day or two you should not be taking responsibility.
She more properly has gastroenteritis.
Most is viral and self limited, and fluid support is essential.
If one can not keep anything down for more than , say, 6 hours , then it becomes dangerous.
The ER, first of all, must treat regardless of her insurance status.
Urgent care is cheaper.
There is frankly not much you as a non doctor can do for her.
There is not much over the counter that helps.
Therefore, err on the side of safety.
If she needs IV fluids, antibiotics, etc...she needs a doctor.
OK, so that is an initial answer….
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