Brief Answer:
Nebulisation provides prompt relief

Detailed Answer:
Hello

Thanks for asking on this platform

I can understand your concern.Most common cause of cough in this age is some viral infection or allergy.Cough is usually associated with some airway spasm which gets improved after nebulisation with bronchodilator(Salbutamol which relieves airway spasm).
Cough can be due to upper airway infection or involvement of lower airways. Nebulisation is not needed each time if cold arises.It is helpful only when there is involvement of lower airway.So it does not causes habituation unless you start giving nebulisation on your own without physician's prescription.
Nebulisation is considered to be safe and effective way of treatment.It is usually prescribed when there is some breathing problem.
There are oral medication like salbutamol syrup which can also relieves airway spasm but side effect is more and it acts slowly.
So I would suggest you to follow the advice of your doctor.

I hope this helps.
Please let me know if you have any more query.
Wishing for you baby's speedy recovery.
Regards

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