Introduction
Depression is a complex disorder associated with a combination of physical, psychological and social factors. It is a treatable illness, for which there are a wide number of treatment options. Depression most often appears for the first time during the prime of life, from ages 24 to 44. One in four women and one in ten men will confront depression at some point in their lives.

Depression is an illness that involves the body, mood, and thoughts. It affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. Depression is not the same as a passing blue mood. It is not a sign of personal weakness or a condition that can be willed or wished away. People with depression cannot merely "pull themselves together" and get better. Without treatment, symptoms can last for weeks, months, or years. Appropriate treatment, however, can help most people who suffer from depression.

The most common symptom of depression is a deep feeling of sadness. People with depression may feel tired, listless, hopeless, helpless, and overwhelmed by life. Simple pleasures are no longer enjoyed, and their world can appear dark and uncontrollable. Emotional and physical withdrawal is a common response of depressed people.

Symptoms of Depression
Not everyone who is depressed experiences every symptom. Some people experience a few symptoms, some many. The severity of symptoms varies with the individual and also varies over time. Depression is diagnosed if a person experiences 1) persistent feelings of sadness or anxiety or 2) loss of interest or pleasure in their usual activities in addition to five or more of the following symptoms for at least 2 weeks.

Depression
· A persistent sad, anxious, or "empty" mood
· Feelings of hopelessness and pessimism
· Feelings of guilt, worthlessness and helplessness
· Loss of interest or pleasure in hobbies and activities that were once enjoyed, including sex
· Decreased energy, fatigue, feeling "slowed down"
· Difficulty concentrating, remembering and making decisions
· Insomnia, early-morning awakening, or oversleeping
· Appetite and/or weight loss or overeating and weight gain
· Thoughts of death or suicide and suicide attempts
· Restlessness, irritability
· Persistent physical symptoms that do not respond to treatment, such as headaches, digestive disorders and chronic pain

Causes of Depression
Several factors play a role in the onset of depression. Very often, a combination of genetic, psychological, and environmental factors is involved in the onset of a depressive disorder.

Biochemistry Deficiencies in two chemicals in the brain, serotonin and noradrenaline, are thought to be responsible for certain symptoms of depression, including anxiety, irritability, and fatigue.

Genetics. Some types of depression run in families, suggesting that a biological vulnerability can be inherited. This seems to be the case with bipolar disorder or manic depression. Additional factors including stresses at home, work, or school can be involved in its onset.

Personality. People with low self-esteem, who are easily overwhelmed by stress, or who are generally pessimistic appear to be vulnerable to depression.

Environmental factors
Continuous exposure to violence, neglect, abuse, or poverty may make people who are already susceptible to depression even more vulnerable to the illness. Serious loss, difficult relationships, financial problems, or any stressful change in life patterns can trigger a depressive episode. It should be noted that depression can still occur under ideal living circumstances.

Heavy drinking can be associated with depressed mood due to the significant depressant effects of alcohol on the nervous system. Individuals suffering from depression sometimes use alcohol to cope with their symptoms, which ultimately worsens their depression and anxiety symptoms.

Medical illnesses such as stroke, a heart attack, cancer, Parkinson's disease, and hormonal disorders can cause depressive illness. They may make the sick person apathetic and unwilling to care for his or her physical needs and prolong the recovery period.

Women experience depression about twice as often as men. Men are less likely to admit to depression, and doctors are less likely to suspect it. The rate of suicide in men is four times that of women, though more women attempt it. Over the age of 70, the rate of men's suicide rises, reaching a peak after age 85.

Depression can also affect the physical health of men differently from women. A study has shown that, although depression is associated with an increased risk of coronary heart disease in both men and women, only men suffer a high death rate.

Treatment of Depression
The person presenting with possible depression should first be seen by their general practitioner. Depending on the severity of that individual’s symptoms, an individualized treatment plan will be drawn up which uses some or all of a number of psychological, biological and social approaches to the problem.

Medications - Antidepressants are medications used in the treatment of depression. Antidepressants are prescribed to correct imbalances in the levels of chemicals in the brain that are present in depression. In individuals suffering from depression associated with Bipolar Disorder and in individuals who suffer from frequent severe mood swings, mood stabilizing medications like Lithium, Sodium Valproate and Carbamazapine are used in the management of recurrent depressive episodes.

There are several types of antidepressant medications used to treat depressive disorders. These include newer medications like the selective serotonin reuptake inhibitors, the serotonin noradrenaline reuptake inhibitors and older antidepressants like the tricyclic antidepressants and the monoamine oxidase inhibitors. It usually takes 3-6 weeks to obtain full antidepressant effect after therapy has begun.

Despite controversy in the media, there is insufficient scientific evidence that antidepressants actually cause people to commit suicide. After two to three weeks on an antidepressant, the energy levels of previously lethargic, depressed individuals can increase dramatically. In individuals with thoughts of self-harm whose depressed thoughts persist this sudden surge in energy may result in acts pf self harm. It is important for patients and relatives and their physicians to be aware of this risk in previously lethargic depressed individuals newly commenced on an antidepressant.

It is important to keep taking medication until it has a chance to work, though side effects may appear before antidepressant activity does. Once the person is feeling better, it is important to continue the medication for at least 4 to 9 months to prevent a recurrence of the depression. For individuals with bipolar disorder or severe recurrent depression, medication may have to be maintained indefinitely.

Antidepressants are not addictive. Abruptly stopping antidepressants is not recommended as this can cause physical discomfort in some individuals, due to what is called discontinuation syndrome. If stopping antidepressants, they should be stopped gradually under the supervision of the doctor.

Side Effects - Antidepressants may cause mild and, usually, temporary side effects in some people. Typically these are annoying, but not serious. However, any unusual reactions or side effects or those that interfere with functioning should be reported to the doctor immediately.

The newer antidepressants, including Selective Serotonin Reuptake Inhibitors and Serotonin Noradrenaline Reuptake Inhibitors may have different types of side effects:
· Headache - this will usually go away.
· Nausea - this is also temporary.
· Nervousness and insomnia (trouble falling asleep or waking often during the night) - these may occur during the first few weeks; dosage reductions or time will usually resolve them.
· Agitation (feeling jittery) - if this happens for the first time after the drug is taken and is very uncomfortable, the doctor should be notified.
· Sexual problems - the doctor should be consulted if the problem is persistent or worrisome.

The most common side effects of Tricyclic Antidepressants, and ways to deal with them, include:
· Dry mouth - it is helpful to drink sips of water. Chew sugar free chewing gum.
· Constipation - bran cereals, fruit, and vegetables may help with this.
· Bladder problems - emptying the bladder may be troublesome, and the urine stream may not be as strong as usual; your doctor should be notified if there is marked difficulty or pain.
· Sexual problems - sexual functioning may change; if problematic, it should be discussed with the doctor.
· Blurred vision - this should pass and should not usually necessitate new glasses.
· Dizziness - rising from the bed or chair slowly is helpful.
· Drowsiness - during the day this usually passes. A person feeling drowsy or sedated should not drive or operate heavy equipment.

Psychotherapy
Psychotherapy, or "talking therapy," may be used either alone for treatment of mild depression or in combination with antidepressant medications for moderate to severe depression.

Psychotherapy can involve only the individual patient or include others. Depending on the severity of the depression, treatment can take a few weeks or substantially longer. However, in many cases, significant improvement can be made in 10-15 sessions.

Talking therapies help patients gain insight into and resolve their problems through talking with the therapist combined with homework assignments between sessions.

Interpersonal therapy and Cognitive/behavioural therapy are two types of short-term psychotherapies that have been shown to be helpful for some forms of depression.

Interpersonal therapy focuses on disturbed personal relationships that both cause and exacerbate the depression.

Cognitive therapy helps change the negative styles of thinking often associated with depression.

Behavioural therapy helps patients learn how to obtain more satisfaction and rewards through their own actions and how to unlearn patterns of behaviour that contribute to or result from their depression.

Family or couple therapy helps to address specific issues that can arise within these close relationships. Group therapy involves people with similar illnesses.

Psychodynamic therapy is long-term therapy that focuses on resolving the patient's conflicted feelings. Psychodynamic therapy is often best used after the depressive symptoms have significantly improved.

In general, severe depressive illnesses, particularly those that are recurrent, will require medication along with, or preceding, psychotherapy for the best outcome.

Electroconvulsive Therapy
Electroconvulsive therapy (E.C.T.) is used sometimes for individuals whose depression is severe or life threatening and needs urgent treatment or for those who cannot take antidepressant medication. E.C.T. is only administered after serious consideration and discussion with the individual patient. For full therapeutic benefit, at least six sessions of E.C.T., given at the rate of two times per week, are required.

During the 1990s, research contributed to a more accurate understanding of ECT. At the same time, methods of anaesthesia and of administering the treatment became more sophisticated and have made the procedure safer.