In my opinion, Levaquin is a dangerous drug. In January 2002, I had a severe cold/sinus infection for which my Dr prescribed Levaquin. I had started a moderate exercise program, and was doing curls with 10 lb dumbbells. I developed SEVERE tendinitis in both elbows within 2 weeks, while taking the drug. I've had cortisone injections, tried stretching, medication, and forearm braces, and nothing has helped. I'm possibly looking at surgery in the near future. My orthopedist was quick to conclude that Levaquin was indeed the cause, combined with the light exercise, which, under normal circumstances, couldn't have possibly caused tendinitis. DO NOT exercise if you're taking this awful drug, and if you're reading this, please get off of it as quickly as you can.