Meredith,
This is less an issue of hiring than of performance on the job. It is unlikely that the employer would KNOW that the person had ADHD at the time they were hired. Employers are not allowed to ask about disability status before making an offer of employment. The bigger issue is whether, once the individual gets on the job, will he/she be able to manage their disability and, if necessary, ask for appropriate accommodation so that they can successfully perform and STAY hired.
Dr. Jane Jarrow