In adults, the main features of ADHD may include difficulty paying attention, impulsiveness and restlessness. Symptoms can range from mild to severe. Many adults with ADHD . Attention deficit hyperactivity disorder (AD/HD) is a common psychological disorder that is characterized by problems with attention, impulsivity and/or hyperactivity. Adults who have significant problems with inattention, but exhibit few or no symptoms of hyperactivity, are said to have the predominantly inattentive subtype of AD/HD. You may also have a learning disability, anxiety or another mood disorder, obsessive compulsive disorder, or a dependence on drugs or alcohol. Knowing the whole picture can make sure you get the best plan for you. Medications to Treat Adult ADHD. Stimulant Medications. Adults with ADHD are often offered stimulant medications.