Brief Answer:
Sextafag helps in preventing bacterial throat infection

Detailed Answer:
Hi

Thanks for asking on this platform

I can understand your concern. Sextafag contains bacteriophage ( uses bacteria as food) and helps in preventing bacterial throat infection.
In children recurrent cold is common due to underdeveloped immunity and poor response to allergens. Viral infections and allergic causes are more common than bacterial one.
As per literature Sextafag helps only in bacterial infection( sore throat,fever).
There are no large research studies approving its use.
In absence of scientific evidences and also considering that recurrent bacterial infections are less common than viral and allergic, I wont suggest you to give this .
I would like to know in detail about his cold symptoms like its frequency, associated symptoms like fever, fast breathing, any allergic skin disorder, family history of allergy etc so that I better able to help you out.
Thnaks

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