Does he have fever, loose motion? There are high chances he may have Acute Gastro-enteritis. With vomiting and loose motions kids tend to loose water as well as
electrolytes..hence make sure he has enough water/ors..keep a watch on the urine output as it indicates the hydration status of the child...He may also need a course of probiotics/antibiotics as per the severity..
Next Steps
1)Visit your nearby paediatrician..to getca detail assessment..2) The doctor will be able to help you out with the correct dosage of medicines as per the weight.
Health Tips
1) Make sure that he drinks plenty of liquids.2) monitor the urine output.