Side effects that are common of generic Ery-Tab include nausea, vomiting, diarrhea, stomach cramping, loss of appetite, and mild heartburn, mouth sores, severe stomach pain, unusual fatigue, dark urine, yellowing eyes or skin, muscle weakness, hearing problems, severe dizziness, fainting, irregular heartbeat, seizures. This medication may rarely cause a severe intestinal condition because of resistant bacteria. This condition may take place during therapy or weeks to months after treatment is over. Avoid using anti-diarrhea products or narcotic pain medicines if you have the following symptoms because these worsen the condition instead of improving it. Notify your local doctor immediately if you develop persistent diarrhea, abdominal cramping or blood/mucus in your stool when using generic Ery-Tab.