I have taken Levaquin for five days for a sinus infection. Day three I started getting muscle soreness. Day four I was so sore I started looking up possible sudden pain. Today I am so sore I can hardly walk and my joints are very painful in my feet,hands and shoulders. I started thinking about what was different and realized the only thing that had changed was that I was taking an antibiotic that I have never taken before. Wow, I am so glad I looked this up. The symptoms that you all are reporting are exactly what I am experiencing! I will never take it again. Hopefully the symptoms will resolve quickly.