For herpes simplex cold sore virus I would try taking around 3000 mg MSM twice a day. This is a powerful immune booster. Read about it. You have to start with 1000 mg twice a day until you detox. Then when the cold sore happens I would try 3 capsules of whole neem leaf twice a day until the sore is gone. I did this and with first dose of neem leaf (3 caps), it died and fell off within three hours and that has been a month and not come back thus far.
I love MSM because my hair had quit growing and I was totally going bald. Also, I stopped having stasis ulcers on my legs and my calf muscles which had been atrophying went back to normal size. MSM increases blood circulation.