You don't have to say ANYTHING about it. If you are legally disabled, you don't need to say what it is, just what "reasonable accomodations" you require.
IF I am ever able to work again, I'm be asking for unpaid sick days. (Sometimes I need 2 - 4 hours to totally regroup, other times I need 2 - 3 days off in a row.) I'll also be asking they accomodate my use of a service dog.
They don't need to know what your diagnosis is, AND THEY CANNOT ASK!
Borderline Personality Disorder
Post Traumatic Stress Disorder
Depakote, Abilify - Fail; Seroquel - Epic Fail
Lamictal 200mg, Seroquel XR 150mg, Klonopin 0.5mg as needed