My father-in-law had been taking Cymbalta for a couple of months for nerve damage due to diabetes. Recently, he was switched to the generic form of Cymbalta, which is duloxetine. His dosage and schedule for taking it has not changed. However, since he switched to the generic, he has been experiencing side effects. The side effects are listed as being associated with both the name brand and the generic forms. He was not experiencing noticeable side effects when taking the name brand. Is this normal? What should he do?