i pulled out my 10th edition2008 THE PILL BOOK what i found is for the yellow round pill Ultram/gerneric nameTramadol mild to moderate pain pill it does say that most common side effect dizziness or fainting, nausea,constipation, headache,tireness,vomiting,itching,weakness,sweating,drymouth(over dose can be deadly) maybe you can talk to him?