Depression is very complex mental state characterized by low mood and aversion to any activity. When person is depressed it is experiencing feelings of sadness, helplessness and hopelessness that prevent this person from functioning properly. In most cases depression is predictable as the response to certain type of life events like for instance loss of person you cared about. Depression is constantly rising in western society and the number of prescriptions written for antidepressants has risen sharply in the last decade. Depression is common side effect present by some diseases like for instance influenza (flu). Large number of patients that suffer from depression have sleeping difficulties. In some cases depression is to put it simply as possible a plea for help. Depression can is some cases, especially if it is frequent lead to serious mental health problems. Medicine still hasn't found what exactly causes depression, only symptoms are known while cause still remains a mystery. The most popular antidepressants are: Prozac (fluoxetine) Zoloft (sertraline) Paxil (paroxetine) Lexapro (escitalopram) Celexa (citalopram) Many antidepressants have rather unpleasant side effects so it is better to avoid them, of course when possible. Antidepressants really treat only the symptoms of depression, so without the further treatment, the underlying cause of their condition will still continue to persist. To fight against depression many people decide to try alternative techniques such as cognitive therapy, subconscious restructuring and mindfulness. In cases of mild depression self evaluation can do the trick in most cases. The most serious form of depression is chronic clinical depression that is characterized by extremely long period of feelings of sadness, helplessness and hopelessness (many months, sometimes even years). People who suffer from this form of depression aren't in most cases aware of their state. Most people that suffer from depression think that they have no way to regain their "normal feelings" feelings and become mentally healthy. source : Facts about depression | Secrets of Healthy Life