My 4yrs Old Son Has Drycoughfreequentlyafter Having Meal Due To

my 4yrs old son has drycoughfreequentlyafter having meal due to cough he vomitted.my dr.gaveascoril plus.. .is dis medicine worked properly..i hav tried lots of medicine..but no results..now m just applying som home remidies lik steaming..garggling...lemon honey syrup...still he suffers a lot...can u give me any advice regarding dis....