Yes! My son is 3. He was diagnosed a few months ago, and was finally able to start treatment last week. In the 3-4 weeks leading up to treatment, there was a huge increase in stuttering, inability to recall common words, inability to maintain a train of thought, lots of "uhhh, ummm, hmmm," and ultimately, lots of, "Mommy, I just don't know what I'm talking about." Broke my heart. When we met with the PANDAS specialist and I told him about the speech issues, he added daily doses of Motrin to his treatment plan. His speech still isn't great, but it's definitely improved from where it was a week ago, before we started the Motrin (and other treatments).
