text: herpes simplex i cold sore is best treated with??   i use l-lysine tablets available from a health food store. it is a natural enzyme & it really works. i take 4 tabs as soon as i feel a sore coming on & then 2 tabs every 2 to 3 hours for the first day, on 2nd day take 2 tabs 3 in the day. it normally never even swells!