Your child must be allergic to cold and sour products and change in climate. Any family history of allergy or asthma?
You can cont with Asthalin syp for few more days
But not getting relief , may require short course of steroid for 3 days but for that you have to consult Pediatrician for checking the chest for wheeze or spasm
Next Steps
Chest XRay if required
Health Tips
Avoid cold products ,banana , guava, sauce , ketchup