Depression is a complex mood disorder, involving many systems of the body, including the immune system, either as cause or effect. It disrupts sleep and one’s appetite; in some cases, it causes weight loss; in others, it contributes to weight gain. Depression is also often accompanied by anxiety. Research indicates that not only do the two conditions co-occur but that they overlap in genetic vulnerability patterns.
feelings of sadness, loneliness, or emptiness that last most of the day for several days on end
loss of interest or pleasure in activities that used to be enjoyable (anhedonia)
tiredness and chronic low energy
difficulty thinking clearly, concentrating, making decisions or remembering
feelings of worthlessness and guilt
feelings of irritability, frustration or anger that are out of proportion with the circumstances
restlessness and agitation
sleep disturbances, including sleeping too much and sleeping too little (insomnia)
change of appetite, most often leading to loss of weight, though some people may have increased appetite and weight gain
Recurrent thoughts of death or suicide, as well as suicide attempts or plans
Psychotherapy, or “talk therapy,” is sometimes used alone for treatment of mild depression; for moderate to severe depression, psychotherapy is often used in along with antidepressant medications. Cognitive behavioral therapy (CBT) has been found to be effective in treating depression. CBT is a form of therapy focused on the present and problem solving. CBT helps a person to recognize distorted thinking and then change behaviors and thinking.
Psychotherapy may involve only the individual, but it can include others. For example, family or couples therapy can help address issues within these close relationships. Group therapy involves people with similar illnesses.
Depending on the severity of the depression, treatment can take a few weeks or much longer. In many cases, significant improvement can be made in 10 to 15 sessions.