Hi Doctor, My 2.9 Year Old Son Has Been Going

Hi Doctor,
My 2.9 year old son has been going to a play school since April this year. Since then he falls sick almost on a weekly basis. Sometimes it is stomach infection while some other time he would throw up and get high fever. My doctor diagnosed it to be common viral attacks due to the weather in New Delhi. He also advised Duolin/Saline Water/Budecort to be given through a nebulizer three times a day to most likely address a relatively long period of dry cough. Aren't these medicines for asthma? I don't have a family history of it. Can't we simply give him steam from boiled water vaporiser instead of pushing medicines down his throat?

Thanks
Tarun