I recently was put on a course of antibiotics for a tooth root infection I had not one clue/symptom that I even had this infection until a mouth x-ray during a dental cleaning.. I was put on Clindamycin after I had the most rare side effects of Amoxicilin which were tightness in chest/dark urine/urine retention..I had doctors arguing with me trying to tell me that those side effects do not exist! I then told them that when it comes to me they need to throw out everything they were taught and improvise since I am an absolute freak of human nature.. So as soon as I stopped the Amoxicillion(against the doctors orders) the tightness in chest/dark urine/urine retention stopped within 24 hours.. The Clindamycine was a godsend for my CFS/ME.. However I did not want to mention anything until the clindamycin cycle was over. While I was on Clindamycin it significantly reduced all of my CFS/POTS symptoms to where I did not need to take my medications such as tramadol/gabapentin/andro gel/ Amitriptyline/Midodrin etc.. I felt as if I were cured!! Soon as I was done with this cycle of Clindamycin ALL of my symptoms came back 10 fold.it seems they are back worse than before the antibiotics.. It also could feel worse because I never had this kind of positive treatment before. Meaning when symptoms came back all at once it was an overload.. I am afraid to mention this to my doctors since they will think I'm insane.. There is one thing I do know... CFS/ME is definitely an unknown debilitating VIRUS! at least with my experience!