is more than just sadness. People with depression may experience a lack of interest and pleasure in daily activities, significant weight loss or gain, insomnia or excessive sleeping, lack of energy, inability to concentrate, feelings of worthlessness or excessive guilt and recurrent thoughts of death or suicide”

an emotion characterized by feelings of tension, worried thoughts and physical changes like increased blood pressure. People with anxiety disorders usually have recurring intrusive thoughts or concerns. They may avoid certain situations out of worry. They may also have physical symptoms such as sweating, trembling, dizziness or a rapid heartbeat.”

or attention-deficit hyperactivity disorder, is a behavioral condition that makes focusing on everyday requests and routines challenging. People with ADHD typically have trouble getting organized, staying focused, making realistic plans and thinking before acting. They may be fidgety, noisy and unable to adapt to changing situations.

is a condition in which the body must have a drug to avoid physical and psychological withdrawal symptoms. Addiction’s first stage is dependence, during which the search for a drug dominates an individual’s life. An addict eventually develops tolerance, which forces the person to consume larger and larger doses of the drug to get the same effect.