I've had CFS for about 10 years but the last 3 have been very bad. I've had to quit my long term career. So, I found online a Dr in Michigan that suggests if there is Epstein Barr present to take 1 gram of Valtrex up to 4 times a day. My blood test results show the Epstein Barr virus in my system. I started taking the Valtrex on August 5th but it became apparent my system was in overload. The 2nd week I took half doses and then resumed on the 3rd. For the last few days I've been as sick as ever. I'm very weak, have horrible brain fog and just recently have a sore throat. I'm wired terribly and have a hard time relaxing. According to the information I read there is a period where you feel worse before you feel better but this is terrible! Supposedly after 6 weeks you start to improve. I'm down now to 2 tablets a day and barely tolerate them. It even seems I continue to worsen though I'm taking much less medicine. Has anyone else experienced similar responses? Thanks so much.