Mental disorders include a wide range of problems, including - Anxiety disorders, including panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, and phobias - Bipolar disorder - Depression - Mood disorders - Personality disorders - Psychotic disorders, including schizophrenia There are many causes of mental disorders. Your genes and family history may play a role. Your life experiences, such as stress or a history of abuse, may also matter. Biological factors can also be part of the cause. A traumatic brain injury can lead to a mental disorder. A mothers exposure to viruses or toxic chemicals while pregnant may play a part. Other factors may increase your risk, such as use of illegal drugs or having a serious medical condition like cancer. Medications and counseling can help many mental disorders. 
What is (are) Mental Disorders ?