Postnatal depression Seasonal affective disorder (SAD) Depression is characterized by persistent feelings of sadness, hopelessness, and loss of interest in life. A number of factors may trigger it, including a stressful life event, such as a bereavement; physical illness or mental health problems; hormonal changes after childbirth (postnatal depression); certain medications; or alcohol or drug abuse. Some people become depressed only during winter months, a condition known as seasonal affective disorder (SAD).
Depression may also sometimes run in families. Depression can cause a wide variety of symptoms, and they may vary in severity from person to person.
Common symptoms include a feeling of sadness, loss of interest in and enjoyment of work and leisure activities, low energy, anxiety, irritability, and low self-esteem.
Other symptoms may include poor concentration, sleeping problems, weight loss or weight gain, reduced sex drive, loss of hope for the future, and thoughts of self-harm or suicide. Mild depression may improve by itself without medical treatment.
In many cases, lifestyle measures may help, such as regular exercise, support from a self-help group, or, for SAD, light therapy. If the depression does not improve with such measures, psychotherapy and antidepressant medication may be prescribed.
If these treatments are ineffective, transcranial magnetic stimulation (stimulating the brain with magnetic fields) or electroconvulsive therapy (passing an electric current through the brain) may be recommended.
A person who is suicidal or a mother who has thoughts of harming her baby requires prompt medical help