Thanks for writing your query.
T-minic contains antiallergic medicine in addition to decongestant.
It should be given for dry cough
with throat congestion
I would suggest that get your child first clinically examined by his Paeditrician and then let his doctor decide which medicine is needed for him.
If there are signs of brochoconstriction , he should be given syrup containing bronchodilators and not cough suppressants.
Also get his throat examined for throat swab culture to know if any infection in throat is also present.
I hope this is helpful to you.