it is also used to treat bipolar disorder tegretol is available in generic form common side effects of tegretol include nausea vomiting dizziness drowsiness dry mouth swollen tongue loss of balance or coordination or unsteadiness as your body adjusts to this medicationt is also used to treat bipolar disorder tegretol is available in generic form common side effects of tegretol include nausea vomiting dizziness drowsiness dry mouth swollen tongue loss of balance or coordination or unsteadiness as your body adjusts to this medication