Brief Answer:
Flucloxacillin only role will be to prevent superinfection from bacteria.

Detailed Answer:
Hi XXXX,

Though flucloxacillin has no direct action against virus causing cold sore, there is no harm to take flucloxacillin in cold sores as it can prevent superinfection from bacteria.

Cold sores are mostly due to herpes simplex virus which can be easily diagnosed by naked eye examination or blood antibody testing for that virus by the dermatologist. Apart from antibiotics, you may take antiviral medications like acyclovir(zovirax) or valacyclovir (valtrex) for rapid healing and prevention of recurrence. You can also take anaesthetic gel (dentogel or zytee gel) if the sore are painful or irritating.

However ,most cold sores does not require any treatment and they get subsided within 7 days if the condition is not severe.

Keep sores clean by washing with saop and water,avoiding taking oily and spicy foods.

You can also apply ice to alleviate pain or burning.

I think I have answered it in more detailed, feel free to ask any query.

Thanks and regards,

Dr.sandipkabra

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