Katherine, 29, looked very focused as she headed to the appointment.
The author carried clothes in a garment bag.
The outing came a day after she skipped out on fiancé Chris Pratt's premiere for "The Kid."
The pair has not said when their wedding will be, but they recently moved in together and were seen looking for home decor at an interior design store in Los Angeles.
What do you think of Katherine's outing? Let us know in the comments.