Most ADHD experts recommend that you NOT disclose your ADHD at work in most situations. While protected by law here in the US, employers can easily get around that.
Instead of going to HR and disclosing your ADHD, work with your close superiors on specific individual struggles. For instance, if you were having trouble focusing due to talking and noise around you, asking for a different office or cubicle placement or using headphones while working…
ADDitude Community Moderator, Author & Mentor on Parenting ADHD, Mom to teen w/ ADHD, LDs, and autism