Depression Support Group

Clinical depression is a state of sadness or melancholia that has advanced to the point of being disruptive to an individual's social functioning and/or activities of daily living. Although a low mood or state of dejection that does not affect functioning is often referred to as depression, clinical depression is a medical diagnosis and is different from the everyday meaning of "being depressed".

Clinical depression affects about 16% of the population on at least one occasion in their lives. The mean age of onset, from a number of studies, is in the late 20s. About twice as many females as males report or receive treatment for clinical depression, though this imbalance is shrinking over the course of recent history; this difference seems to completely disappear after the age of 50 - 55, when most females have passed the end of menopause. Clinical depression is currently the leading cause of disability in the US as well as other countries, and is expected to become the second leading cause of disability worldwide (after heart disease) by the year 2020, according to the World Health Organization.

There are a variety of types of depression, including clinical depression, seasonal affective disorder (SAD), and postpartum depression.

DSM-IV-TR criteria for diagnosing a major depressive disorder one of the following two elements must be present for a period of at least two weeks (See the DSM cautionary statement.): Depressed mood, or loss of interest or pleasure in nearly all activities.

It is sufficient to have either of these symptoms in conjunction with five of a list of other symptoms over a two-week period. These include:

• Feelings of overwhelming sadness or fear or the seeming inability to feel emotion (emptiness).
• Changing appetite and marked weight gain or loss.
• Disturbed sleep patterns, such as insomnia, loss of REM sleep, or excessive sleep (Hypersomnia).
• Psychomotor agitation or retardation nearly everyday.
• Fatigue, mental or physical, also loss of energy.
• Feelings of guilt, helplessness, hopelessness, anxiety, or fear.
• Trouble concentrating or making decisions or a generalized slowing and obtunding of cognition, including memory.
• Recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan, or a suicide attempt or a specific plan for committing suicide.

Treatment of depression varies broadly and is different for each individual. Various types and combinations of treatments may have to be tried. There are two primary modes of treatment, typically used in conjunction: medication and psychotherapy. A third treatment, electroconvulsive therapy (ECT), may be used when chemical treatment fails.

Medication that relieves the symptoms of depression has been available for several decades. These drugs are listed in order of historical development. Typical first-line therapy for depression is the use of an SSRI, such as sertraline (Zoloft).

Monoamine oxidase inhibitors (MAOIs) such as Nardil may be used if other antidepressant medications are ineffective. Because there are potentially fatal interactions between this class of medication and certain foods and drugs, they are rarely prescribed anymore. MAOI's are used to block the enzyme monoamine oxidase which breaks down neurotransmitters such as serotonin and norepinephrine.MAOI's are as effective as tricyclics, if not slightly more effective. A new MAOI has recently been introduced. Moclobemide (Manerix), known as a reversible inhibitor of monoamine oxidase A (RIMA), follows a very specific chemical pathway and does not require a special diet.

Tricyclic antidepressants are the oldest and include such medications as amitriptyline and desipramine. Tricyclics block the reuptake of certain neurotransmitters such as norepinephrine and serotonin. They are used less commonly now because of their side effects, which include increased heart rate, drowsiness, dry mouth,constipation, urinary retention, blurred vision,dizziness, confusion, and sexual dysfunction. Most importantly, they have a high potential to be lethal in moderate overdose. However, tricyclic antidepressants are still used because of their high potency, especially in severe cases of clinical depression.

Selective serotonin reuptake inhibitors (SSRIs) are a family of antidepressant considered to be the current standard of drug treatment. It is thought that one cause of depression is an inadequate amount of serotonin, a chemical used in the brain to transmit signals between neurons. SSRIs are said to work by preventing the reabsorption of serotonin by the nerve cell, thus maintaining the levels the brain needs to function effectively, although two researchers recently demonstrated that this is a marketing technique rather than a scientific portrayal of how the drugs actually work. Recent research indicates that these drugs may interact with transcription factors known as "clock genes", which may be important for the addictive properties of drugs of abuse and possibly in obesity.

This family of drugs includes fluoxetine (Prozac), paroxetine (Paxil), escitalopram (Lexapro), citalopram (Celexa), and sertraline (Zoloft). These antidepressants typically have fewer adverse side effects than the tricyclics or the MAOIs, although such effects as drowsiness, dry mouth, nervousness, anxiety, insomnia, decreased appetite, and decreased ability to function sexually may occur. Some side effects may decrease as a person adjusts to the drug, but other side effects may be persistent.

Norepinephrine reuptake inhibitors such as reboxetine (Edronax) act via norepinephrine (also known as noradrenaline). NeRIs are thought to have a positive effect on concentration and motivation in particular.

Serotonin-norepinephrine reuptake inhibitors (SNRIs) such as venlafaxine (Effexor) and duloxetine (Cymbalta) are a newer form of antidepressant that works on both noradrenaline and serotonin. They typically have similar side effects to the SSRIs, although there may be a withdrawal syndrome on discontinuation that may necessitate dosage tapering.

On 28 February 2006, the United States Food and Drug Administration approved Emsam, a transdermal MAOI patch developed by British company Somerset Pharmaceuticals, to be marketed in the U.S. by Bristol-Myers Squibb.

For further reading, you might try: the depression section of Medline Plus, Mayo Clinic's depression center.