I was prescribed a generic, Levofloxacin, for an antibiotic resistant infection in a surgical wound. After reading side effects I was hesitant to take it, but it is 100 times more effective than other antibiotics for enterobacter and I had a deep ulcerated wound. I questioned doc about the side effects, he said in 20 yrs he'd never had anyone report negative side effects, so, I started the medication, a 14 day RX 500mg once daily. Immediately had horrible indigestion, sleeplessness, muscular weakness, could barely walk 10 steps then had to sit down for a couple minutes to rest and catch breath, tendons in fingers and shoulders started swelling, and one knee is now feeling swollen and I hear a poppig in it which sounds/feels like a swollen tendon. I am 66, athletic, accustomed to walking in the mountains about 3 miles a couple times a week and ride horses for 25 mile rides a couple times a week, I lift 50lb feed bags and move around 110# bales of hay, so I KNOW when something is not right. I had to take double dose of sleeping pills to be able to rest at all, would sleep a few hrs, then wake up with both shoulders having tendon pain and sometimes the hips. I stopped the meds yesterday and will be contacting the reporting agency for negative side effects. So far, no issues with Achilles tendons yet and I am praying that the tendon issues will resolve quickly.