Brief Answer:
Could be viral or allergic

Detailed Answer:
Hi
Thanks for writing to us.
From your short description your baby seems to have cold and cough.
Is there any fever ?
How long is the baby having these symptoms?
Any breathing difficulty, fast breathing , chest in drawing ?
How is the feeding, urination, general activity ?
If the baby is healthy, active, no other symptoms and no distress , then no need to worry.
Usually medicines are not required at this age unless warranted.
I usually suggest nasal saline drops 1 drop each nostril three or four times daily before feeding.
If baby develops any other abovementioned symptoms or fever or distress, take to doctor immediately for physical examination.
Feed frequently to keep baby hydrated. Usual duration for this upper respiratory problem is 3 to 5 days , mostly will settle on its own.
Regards
Dr Arun

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