OP here. Thanks to those who replied. Just seems like, in the past week or so, DS couldn't help but say every thought that came into his head. I usually love listening to his thoughts and ideas, but sometimes we're trying to leave the house in a rush, or someone else is trying to talk. I feel guilty when I ask him to stop talking so much. It was a little better today, though. I think the medication is just right, but we're having a rough go of things this past week. Suspect it's just the change of a new school year.
I'm so glad to have this forum to reach out to other parents of kids with ADHD. Our kids are amazing in so many ways, but some days are harder than others!