Depression affects the way a person feels about himself, how he eats and sleeps, and how he thinks about things. Most people suffering from depression have overwhelming feelings of sadness, hopelessness, and helpessness. Suicide is a danger if you are depressed.

Alternative Names
Depression - major; Unipolar depression; Major depressive disorder

Causes, incidence, and risk factors
The exact cause of depression is not known. Some researchers think that it may be caused by chemical imbalances in the brain, which may be hereditary or caused by events in a person’s life.

Some types of depression seem to run in families, but depression can also occur in people who have no family history of the illness. Stressful life changes or events can also trigger depression in some people. Usually a combination of psychological, environmental, and hereditary factors are involved in the development depression.

Major depression occurs in all groups of people, and it is more common than you might realize. Each year, more than 18 million Americans - men and women of all ages, races, and economic levels - suffer from depression. There is an increased incidence in women.

Many women are especially vulnerable to depression after giving birth as a result of the hormonal and physical changes that they have experienced. While new mothers may commonly experience transitory “blues”, depression is not normal and requires treatment.

Depression can also be seen in adolescents and children, and they can also benefit from treatment.

Symptoms

 
• Persistent sadness lasting greater than 2 weeks.  
• Loss of interest or pleasure in activities that were once enjoyed (including sex).  
• Loss of appetite and/or weight loss, or overeating and weight gain.  
• Sleep disturbances.  
• Energy loss or fatigue.  
• Behavior that is either slowed down or restless.  
• Feelings of worthlessness, hopelessness, and pessimism.  
• Difficulty concentrating, making decisions, and remembering.  
• Thoughts of death or suicide.  
• In some cultures, physical discomfort, weakness, and “nerves” may be the most prominent symptoms.  
• In children and adolescents, mood is more likely to be irritable (see adolescent depression).  
• If depression is quite severe, it may be accompanied by psychotic symptoms, such as hallucinations and delusions. These are usually consistent with the depressed mood, and may focus on themes of guilt, personal inadequacy, or disease.  
• Depression can also appear as irritability, anger, and discouragement rather than feelings of hopelessness and helplessness.

Signs and tests

 
• The history of persistent sad mood, loss of interest or pleasure in activities that were once enjoyed, and several of the additional symptoms listed above, are required to make the diagnosis of depression.  
• The Beck’s Depression Scale Inventory, or other screening tests for depression can also be helpful in diagnosing depression.  
• Medical causes that can show symptoms of depression should also be ruled out before making the diagnosis of depression.

Treatment
Depression can be treated with medications and/or with counseling. Most people benefit from a combination of the two. Some studies have shown that antidepressant drug therapy combined with psychotherapy appears to have better results than either therapy alone.

Medications include: tricyclic antidepressants, monoamine oxidase inhibitors, selective serotonin re-uptake inhibitors (SSRIs), and some newer antidepressant drugs. Lithium and thyroid supplements may be needed to enhance the effectiveness of antidepressants. For persons with psychotic symptoms, such as delusions or hallucinations, antipsychotic medications may be needed.

Types of psychotherapy that have proven to be particularly effective for treating depression include interpersonal therapy, group therapy and cognitive/behavioral therapy. Antidepressant drug therapy combined with psychotherapy appears to have better results than either therapy alone.

Electroconvulsive therapy (ECT) is a treatment that causes a central nervous system seizure by means of an electrical current. ECT may improve the mood of severely depressed or suicidal people who don’t respond to other treatments.

Research is now being conducted on transcranial magnetic stimulation (TMS), which alters brain functioning in a way similar to ECT, but with fewer side effects. Use of light therapy for depressive symptoms in the winter months and interventions to restore a normal sleep cycle may be effective in relieving depression.

As treatment takes effect, negative thinking diminishes. It takes time to feel better, but there are usually day-to-day improvements. It is important to maintain a healthy lifestyle, including: good nutrition, avoidance of alcohol and drugs (which make depression worse and may interfere with medications), regular exercise and sleep, and involvement in supportive interpersonal relationships.

Over the last decade, the use of herbal products has increased tremendously. Most consumers use herbal products for management of chronic conditions, such as psychiatry disorders, including anxiety and depression.

St. John’s wort (hypericum) has a long history of use in Germany and has recently gained popularity as an adjunct antidepressant in the United States. Most of the German studies indicated a comparable wanted effect with use as tricyclic antidepressants, and better desired effects than placebo (sugar pill).

The National Institute of Mental Health and the National Center for Complementary and Alternative Medicine have recently sponsored the Hypericum Clinical Trial.

The multi-center, randomized, controlled study aims to compare 50 to 150 mg/day of Sertraline (Zoloft), 900 to 1800 mg/day of St. John’s wort, and placebo in 330 patients with major depression. The result of this large clinical trial will provide a better perspective of the role of St. John’s wort in depression.

Side effects associated with the use of St. John’s wort are usually mild and primarily include gastrointestinal symptoms and fatigue. Photosensitization is a common side effect, especially in light-sensitive individuals and/or with high dosage (1800 mg/day).

Fortunately, the effect is reversible within a few days of drug discontinuation. St. John’s wort has been reported to interact with cyclosporine, warfarin (coumadin), and digoxin, with a decrease in concentration occurring with all the affected medications.

Close monitoring of drug levels and laboratory tests, such as INR, are advised if concurrent use is necessary. Contraindications to its use include pregnancy, lactation, and exposure to strong sunlight. Patients should tell their doctors about the use of herbal products.

Support Groups
The stress of illness can often be helped by joining a support group where members share common experiences and problems. See depression - support group.

Expectations (prognosis)
The outcome is usually good with treatment. Although most depressive episodes can be effectively treated with either medication, psychotherapy, or both, depression is a recurring problem for many people. For people who have experienced repeated episodes of depression, maintenance treatment may be needed to prevent future recurrences.

Complications

 
• Suicide (up to 15% of people with major depressive disorder die by suicide)  
• Increased risk of alcohol- and/or drug-related problems  
• Increased risk of tobacco dependence  
• Increased risk of problems with physical health and premature death due to medical illness

Calling your health care provider
Call your health care provider or mental health professional if any of the symptoms are interfering with your ability to function. It is especially important to call your doctor if you feel like life is not worth living, or if thoughts of harming yourself come to your mind.

Prevention
Some episodes of depression can be avoided by learning effective stress management techniques; avoiding overuse of alcohol, drugs, and caffeine; exercising regularly; and maintaining good sleep habits. Many episodes of depression are not preventable. Treatment, including medications and psychiatric intervention, may prevent recurrences.