Brief Answer:
It is contraindicated in infants

Detailed Answer:
Hello

Thanks for the query

I do understand your concern.Rhinathiol yellow syrup is used in children for cough to loosen the thick mucus; but it is contraindicated in infants (below one year of age).
Rhinathiol contains carbocisteine a mucolytic and promethazine an antiallergic.
Promethazine can cause respiratory depression in infants.Although the incidence is very low but better it's use should be avoided.
The common cause of cough in this age is viral or bacterial infection.The better alternative is some bronchodilator like salbutamol with mucolytic and antiallergic like chlorpheniramine.
If used the dose of 2 ml of rhinathiol for 5 month old baby is appropriate.

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

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