... to which I took OTC pain meds (Tylenol & Aspirin) but it didn't help with the leg or back pain. I will throw in that I was assaulted and taking Truvada & Isentress is part of the hospital's protocol to prevent HIV infection. Yesterday my back and legs started hurting pretty severely, and this morning I can barely stand up and walk because the muscle pain in my legs is so bad. Should I just call my doctor's office & take them the paperwork I received when I was prescribed the Truvada or do I just wait it out or should I call an ambulance? There's a section that says 'severe and sometimes fatal lactic acidosis may occur' and to call the doctor immediately. Any thoughts?