described in the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders. They are:
Poor appetite and significant weight loss, or increased appetite and significant weight gain.
Insomnia or increased sleep.
Agitation or retardation of movement and thought.
Loss of interest or pleasure in usual activities or decrease in sexual drive.
Fatigue and loss of energy.
Feelings of worthlessness, self-reproach or excessive or inappropriate guilt.
Diminished ability to think or concentrate; indecisiveness.
Recurrent thoughts of death or suicide; or suicide attempts.
Not all of these characteristics occur in each individual who becomes depressed. For purposes of psychiatric treatment, a person is considered to have experienced a major depressive episode if he or she exhibits a loss of interest or pleasure in all or almost all usual activities and shows at least four of the above symptoms nearly every day for a period of at least two weeks. The term depression is often modified by words that imply either some specific factor or some chemical mechanism is the cause of the state.
Depressions that are reactions to some loss of or separation from a valued person or object are called reactive (or exogenous) depressions.
This contrasts with the usually more severe depressions without apparent cause, called endogenous depressions, or those accompanied by delusions.
Specific remedies for depression
St. John's wort (hypericum) has a long tradition of use in Europe, and while it sometimes gets remarkable results