Adult attention-deficit/hyperactivity disorder (ADHD) is a mental health illness characterized by a number of chronic issues, including trouble paying attention, hyperactivity, and impulsive conduct.
Bipolar disorder, formerly known as manic depression, is a mental illness characterized by significant mood fluctuations that include emotional highs (mania or hypomania) and lows (depression).
Nicotine withdrawal is the physical and psychological symptoms you feel as nicotine leaves your body. Symptoms include the urge for nicotine, irritation, frustration, trouble sleeping and trouble concentrating.