Hi, I'm so sorry to hear about your sweetie's skin problem! I deal with cold sores too and have done a lot of research. The one thing that gives me solace is that doctors say that the outbreaks deminish (sp?) with age! I just know you will find a system that will help your baby deal with them.
One thing I thought I would mention, I also take Lysine but have probs taking the tablets I find at the drug store so I order capsules online that are much easier to swallow, anyway...you might want to look into the capsules as you could maybe open them up and sprinkle it in his food as a way to get it into him! :)
In England they have a new product called Compeed that is a patch that covers the sore. It is also supposed to hide the sore. I'm really interesed in THAT! (helps to prevent spreading too) I haven't been able find a way to purchase it YET, but I haven't looked lately. Orajel has come out with a sort of copy-cat product that is an overnite patch. I'm not too interested in that because in my many years of dealing with this the key is to DRY it out and this says it "moisterizes". And it is just for overnite.
I must stress that it has helped A LOT when I discovered using ice on it just as it is starting. The ice seems to confuse the virus and sometimes it will stop altogether. The hard part for you will be getting your kiddo to keep the ice on it! :-P
I go hard-core on the whole drying out idea...I used to use rubbing alcohol (yeah, I know...drastic.) But I have found one of the best things to use is something sold at Walgreens called "Cure-chrome" antiseptic. (it is in the first aid section) At the first sign of outbreak you wet a q-tip with the cure-chrome and gently rub the liquid into the blisters. It is the gentle rubbing that delivers the medicine into the skin. Don't rub so hard as to damage the skin tho. And don't dip the q-tip back into the bottle, of course. I do this for about 10 minutes--then leave it alone for one hour before putting on Abreva or Camphoponique (sp?) I'll reapply later in the day if it seems to be a particularly bad outbreak. Once again, it might sting a bit so I don't know if you want to try this.
Hope all this rambling helps in some small way. Sending a hug to your sweet little guy!
L.