Hi, My Kid Is 2.5 Years Old And Suffering From

Hi, my kid is 2.5 years old and suffering from cold and cough from last 1 week. Initially he was not having chest congestion but it developed after 3-4 days of cold. Doctor has prescribed Asthalin syrup. Is it fine if I give such strong syrup to 2.5 yr old kid? Also kindly suggest if it is an addictive drug or not?