Brief Answer:
Need more info

Detailed Answer:
Hello and Welcome

I appreciate your concern

Based on the information you provided , I would like to gather some more information

Have you recently suffered from herpes infection ?
Are you immune competent , meaning do you have any immune compromising condition such as HIV or malignancy or a history of either ?
If appropriate ,Can you upload a good quality image of the cold sore that you described ?


Wishing you best of health

Thanks

Please consult your doctor before deciding on any further course of action.

Dr. M.S. Khalil

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Brief Answer:
Famciclovir only if its a confirmed case of Herpes Labialis

Detailed Answer:
Hello again

If it's a confirmed case of Herpes Labialis then in case of recurrent episodes therapy can be initiated within the 1st hour of symptoms such as itching or burning, in consult with your doctor. Supressive therapy can be started if the episodes occur more frequently i.e 250 mg PO q12hr for a period of 12 months. If its just due to stress then the most likely diagnosis is recurrent Aphthous ulcer. Then again, an image of the lesion would help in clarifying the situation a little more. If appropriate please upload an image of the area having the cold sore.

Let me know if you have any query

Thanks.

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