Brief Answer:
Get him clinically evaluated by a pediatrician

Detailed Answer:
Hello

Thanks for asking on this platform


You are right mam.Sudden onset of cough without any cold symptoms,which is continuous in this age group can be due to some foreign body inhalation into the respiratory tract.
Although baby of this age are predominantly breast fed but due to their mouthing habit which develops at this age there are chances of foreign body inhalation.A clear history is also difficult to get in this age.
Baby may remain active and feed normally if the object is not in main bronchus.Sometimes it is really very difficult for the parents to assess and thus the child should get evaluated by a pediatrician in the presence of this symptom and if there is suspicion.
On clinical examination there may be decreased air entry on one side of chest and on X ray there can be hyperinflation or collapse.

So I suggest you to get him clinically examined by a pediatrician to rule out the possibility of foreign body if any.

All the best.
Wishing for your baby's good health.
Regards

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Brief Answer:
Possibility of foreign body should be ruled out

Detailed Answer:
Thanks for writing back

Yeah,it can be due to other causes.But in this scenario possibility of foreign body should be ruled out.
It can be detected clinically or by Xray.Sometimes CT chest or direct bronchoscope examination may be needed depending on the situation.
Once detected in most of the cases it can be removed through bronchoscope(an instrument like endoscope with camera) under general anesthesia.Very rarely surgery may be needed.

Please let me know about the further proceedings.
Good luck.
Regards

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