Depression is a condition in which there is imbalance in the brain's signaling chemicals. The causes of depression are not fully understood. However, there are several theories about what this imbalance actually is and which signaling chemicals are involved. Moreover, a variety of distressing life situations are also associated, including early childhood trauma, a job loss, the death of a loved one, financial troubles, or a divorce. The inability to achieve one's goal and extra work may cause the level of noradrenaline low, as a result the signal-sending activity becomes low. Tranquilizers such as Equanil can help in treating depression.