Horrible side effects. Had sinus infection so was also taking Avelox, took 2 tramadol for pain for 3 bulging discs and face pain associated with sinus infection. Pills were spaced out over 7 hours. Then BAM I wake up about 3:30 a.m. itching all over and then progress to vertigo and nausea. The Avelox brought its own set of symptom, which I didn't realize for a few days after the Tramadol was out of my system. The whole experience sent me to the urgent care, then by ambulance to hospital. I HATE TAKING MEDS.