i have just got over a terrible dose of cold sores on my lips about five blisters in all, i do suffer from herpes simplex but i had a sunbed 4 weeks ago and i reckon the sunbed was too strong and that brought it on, have also heard that dirty unclean sunbeds in parlours can cause cold sores. maybe its the change in the weather ? who knows. anyway after the last episode i will definately be applying an anti viral ointment at the very first itch/signs/tingling of a cold sore. they look filthy and dirty and i dont want to go through that again. ive learnt my lesson as i usually just ignored the first signs.