Some side effects associated with generic Avidoxy are severe headache, dizziness, blurred vision; fever, chills, body aches, flu symptoms; severe blistering, peeling, and red skin rash; urinating less than usual or not at all; pale or yellowed skin, dark colored urine, fever, confusion or weakness; severe pain in your upper stomach spreading to your back, nausea and vomiting, fast heart rate; loss of appetite, jaundice, easy bruising or bleeding, unusual weakness, swollen tongue, trouble swallowing; mild nausea, vomiting, diarrhea, or stomach upset; white patches or sores inside your mouth or on your lips; sores or swelling in your rectal or genital area; or vaginal itching or discharge.