This medication may cause severe allergies resulting in death. Stop this medication if you develop a rash and any of the side effects listed and contact your doctor immediately. It can also lead to serious liver damage and lactic acidosis. Keep all your appointments and go in for regular lab check ups as advised. Inform your doctor if you have or have ever had liver diseases, or drink large amounts of alcohol. If you notice yellowing of the skin, unusual bleeding, bruising of the skin, pain in the upper right hand part of the stomach, contact your doctor immediately.