Brief Answer:
Observe the condition closely

Detailed Answer:
Hello

Thanks for asking on this platform

I have gone through the details and understand your concern well.
This appears to be a case of food poisoning with gastroenteritis.
Here the main aim of management is to maintain adequate hydration.
So the first step of management is to stop the vomiting to increase the oral acceptance of fluids.
In case of severe vomiting child may not tolerate even the oral medication and thus antiemetic injection may be needed.
As you have mentioned it appears to be a case of severe vomiting and if it persists get him to the physician for injectable antiemetic.Once it improves you can give domstal (domperidone)syrup to control the further episodes of vomiting.For this age dose of 5-7.5 ml of domstal will be sufficient.

As most of the food poisoning is due to bacterial or amebic infection giving cefixime with metronidazole do.
The dose of cefixime for this age considering weight of 15-20 kg, would be 100 mg twice a day.Similarly dose of metronidazole would be 5 ml(each 5 ml contains 200 mg) three times a day.You can give paracetamol 5 ml (each 5 ml contains 250 mg)for fever.
All these are prescription medication so please get it prescribed by a physician.
Give him plenty of fluids (ORS) to avoid dehydration.
If vomiting persists,frequency of stool is very high,oral acceptance is poor,urinary frequency is decreased or child is getting lethargic take him to the pediatrician for evaluation and management accordingly.

I hope this helps.
Please let me know if you have any more query.
Wishing for your child's speedy recovery.
Regards

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