Alternative Medicine/Cold sore


Hi Dr. Brandt,

My son accidentally used my toothbrush and I just had a cold sore come out.  He has a paediatric disorder (not relevant to you), which leaves me worried and desperately trying to minimize an outbreak.  I have given him 2g twice a day of Valtrex form1 day, which is often given at first sign of a cold sore in an effort to minimize lesions.  My question is this.....did I do this in vain since there is no sign of a cold sore yet?  Would it be beneficial to continue giving him Valtrex for a week (during incubation phase), maybe at a lower dose and then give him the higher dose again if he starts getting a cold sore?  Or would the best option have been to just wait until signs of a cold sore were present?  What would the best regime be to minimize outbreak for my son?

I can't find a dermatologist on this site.

Thank you,
Worried mama.

Hi Diane,
Valtrex should be used if a person is symptomatic. Preventative treatment is used if there is frequent recurrent infections. I would wait for symptoms before treating. Cold sores are not life threatening.
Thank you for using Allexperts.
Eric Brandt, B.Sc. Pharm

Alternative Medicine

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Eric Brandt


I will answer questions regarding prescripion and non prescription drugs as well as commonly used mdicinal herbs. I will also answer questions on various medical conditions such as heart disease, hypertension, thyroid problems, diabets, menopause, parkinson`s disease, multiple sclerosis, depression etc.


I am a practicing hospital pharmacist with 10 years experience in hospital and 10 years retail pharmacy experience prior to that.
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