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Detailed Answer:

Hi,

- Relent syrup is given for relieving allergy &mucolytic purposes(to treat asthma/bronchitis)or allergic manifestations.... provided the child is not allergic to ambroxol/absence of liver or kidney problem.
- The anti allergic content (cetrizine) is likely to cause drowsiness...so care is needed while giving it to child.I understand your concern.
* A four years. child can be given 0.5 ml. (or 1/8th of tea spoon) two or three times a day as per gravity of his symptoms . Let him take rest,have light nurishing food,drink hot water only.
Please observe for any side effects like drowsiness,nausea-vomitting,rashes.
* Dosage may be altered according to his body weight, severity of symptoms. also signs of intollerance(as described above) may call for change of dosage or drug itself.
*So to start with start give him 0.5ml of the medicine 12 hourly .. preferably after food.Observe for the relief. If it is not satisfactory or some side effects are seen... take him to his pediatritian for specific dosage to be applied to the child.

I hope that helps you. Any follow up query is welcome.
Thanks.

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