Hi,
Recurrent
cold cough with nocturnal exacerbation is an allergic
bronchitis or asthamtic bronchitis after having ruled out infections.Such Bronchitis happens if there is a family history in parents ,air pollution,various allergens in food and environment.Since the docter has prescribed oral medication he is likely to be in milder grade.The medication might help him if taken properly .If doesnot improve then he might require Metered dose inhalers which only the docter would be able to assess as to when to start.So at present keep a regular follow up with the docter.
Bye
Take Care