Fact box: depression

So, since anxiety and depression is the most commonly occurring mental health issue I figured I'd start my fact box series there. Depression today, anxiety to follow (sounds like the weather forecast to my life Haha).

Names depression, major depression, major depressive disorder, MDD, unipolar depression, clinical depression.
Symptoms include
Low mood, pessimism, Tearfulness
Apathy, lack of motivation, low energy
Poor memory and concentration
Irritability and anger
Lack of interest in enjoyable activities and reduced sex drive
Low self esteem and self worth
Feelings of hopelessness and worthlessness, pessimism
Changes in sleeping and eating patterns
Lack of self care and personal grooming
Poor coping strategies- drugs, alcohol, self harm
Thoughts of suicide or harming oneself
Social isolation and reduced interaction, withdrawal

Amongst others. There are certain common recurring features but everyone's experience is different.

Diagnosis
The first port of call for symptoms of depression is usually your gp (or equivalent).
A decent gp should listen to you and probably ask you to fill in a couple if quick diagnostic tests (and no not ALL of them are, they're human too....But that's another post and I'd never discourage someone from seeking help simply because of the possibility of a bad reaction).
The most common of these are the patient health questionnaire-9 and the Beck depression inventory, though there are many similar ones used. They will simply ask you to rate how often you've noticed certain characteristic symptoms over the last two weeks, and how much this has affected your life. The over two weeks but is part of the diagnostic criteria (as per DSM-IV) though some people may be suffering for a lot longer before seeking help.
These tests are a basic way of screening for depression and giving a rough gauge of the severity of the condition, along the way your present to the Dr and the things to share with them.
Treatment
Depending on factors such as severity, risk (to self or dependents) and social/family support your gp may treat you themselves without initially referring you.
This could be through online self help or self help workbooks, exercise, or medications (more below).
Alternatively you may be referred on for more specialist assessment and treatment by qualified mental health professionals. This can include:
Cognitive behavioural therapy (cbt) which aims to identify and change unhelpful patterns of thinking and behaviour.
Counselling which encourages patients to talk through worries with an impartial professional
Community psychiatric teams such as home treatment teams who can support those who are struggling to carry out tasks for every day living
Psychiatrists who are specialised mental health doctors and able to prescribe medications that a gp may be less familiar with.

Ah, yes, medications.
Antidepressants the most common antidepressants used these days come from a group called selective serotonin reuptake inhibitors, SSRIs (fluoxetine, citalopram etc). As the name suggests they treat depression by increasing levels of serotonin in the brain, which seems to alleviate the symptoms of depression. They generally have fewer side effects than older tricyclic antidepressants, though headaches, nausea, anxiety and changes in sleep, appetite and sex drive are reasonably common but tend to decrease after the first few weeks.
Medications can be effective but are only recommended for moderate to severe cases, and may take several weeks to take effect.
Less commonly other forms of psychotropic drug such as antipsychotic drugs (risperidone olanzapine),  or mood stabilisers (lithium, lamotrigine) may be used in conjunction with antidepressants. This is more common in enduring cases where the usual treatments have had little effect.

Even less commonly more drastic treatments such as hospitalisation, electroconvulsive therapy or deep brain stimulation made be used. There is plenty of info around on these but such complex therapies are not something that should really be discussed with professionals not by me on a blog (I'm all for speaking out about mh but some times one can do more harm than good by sharing incomplete information).

Statistics
2.6 per cent of people in England will experience depression, this rises to nearly 10 per cent for mixed anxiety and depression
1 in 20 will suffer diagnosable depression at any given time (both taken from mind.org)
A WHO study found that depression has a greater impact on personal wellbeing than conditions such as angina or diabetes.

Related conditions
Mixed anxiety and depression (MAD)
bipolar disorder
Seasonal affective disorder (SAD)
Post natal depression
Dysthemia

Links
The depression alliance
Depression UK
Moodjuice (online self help)
NHS choices depression page

Phew that's longer than intended, I'll try to get more succinct I promise. It's getting late so if any of the links don't work let me know and I'll try fix. Also if there are any sites you've tried that you would like to share let me know and I'll add them.... same for anxiety which as mentioned is coming next.