Depression is a psychological condition that changes how people think and feel, and also affects social behavior and sense of physical well-being. Depression is the most common and most serious mental health problem facing people today. While it is normal to experience feelings of sadness every now and then, depression occurs when these feelings last for long periods of time. For example, for several weeks to several years but this is considering if it is left untreated. Depression interferes with a person's ability to function well through out the day or even to have the motivation to get out of bed in the morning. No person is immune from depression it occurs in people of all social classes, all countries, and all cultural settings. About half of all cases of depression are unrecognized or untreated. There are many different symptoms caused by depression, some of them are sad mood, sleep problems, appetite change, concentration loss, suicidal thoughts, anxious, empty mood, feelings of hopelessness, pessimism, feelings of guilt, worthlessness, helplessness, loss of interest or pleasure in hobbies and activities that were once enjoyed, including sex, decreased energy, fatigue, being "slowed down", difficulty concentrating, difficulty remembering and making decisions, insomnia, early-morning awakening or oversleeping, appetite or weight loss or overeating, weight gain, thoughts of death or suicide attempts, restlessness, irritability, persistent physical symptoms that do not respond to treatment, such as headaches, digestive disorders, and chronic pain.(Are you Considering Meds for Depression, 1) There are many different kinds of treatment for depression, medications are the most rapid way to treat these symptoms which are treated with antidepressants that are categorized in three major types of antidepressants; TCAs, MAOIs, and SSRIs. Research shows that the most effective antidepressant is Selective Serotonin Reuptake Inhibitors (SSRIs) because it has shown to be the most acceptable antidepressant there is.