Brief Answer:
follow the advises... observe how she stays after this...

Detailed Answer:

Hello,

Well, it seems she's been prescribed the right medications only...Please note at this age group, gastroenteritis mostly due to viral infections, and it'll subside on its own (within a time period of 3-5 days, can even prolong up to a week or so in some individuals)...

The most important part is to avoid dehydration, give her plenty of ORS solution (WHO-ORS solution XXXXXXX dilute in one liter of mineral water and make her drink it as much as she wants)...Repeat the same for multiple times throughout the day for next 2-3 days and observe how she stays after this...

Additionally, you may continue the Gnorm powder as already advised by her doctor...It's extremely important to be vigilant about the urine output and overall improvement...Observe for the oral intake, encourage to drink mineral water, juice, ORS-solution as much as possible...maintain proper hand hygiene before and after using the washroom, drink only Mineral/U.V.RO purified water...Let her take simple curd-based foods and plenty of juice, soups etc.

If despite following this there's no improvement or any further deterioration of the overall condition, lethargy, irritability, poor oral intake, then I'd suggest not to delay any further and take her to the nearest Children's hospital as in that case, further fluid and electrolyte replacement need to be started intravenously...

Let me know if I can assist you further...

Take Care
Kind Regards

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