Anxiety is a normal and healthy part of life. Each one of us has been anxious and fearful at one time or another, and everyone can identify with the unique feelings associated with it.

But what if that feeling occurs on occasions where there is nothing to fear? What if that feeling keeps recurring, leaving you permanently on edge? Or when a specific worry turns into an obsession? Anxiety can take over your life, and it is at this point that it becomes something more than a natural emotion.

	What Happens When You Panic?

Here are how other h2g2 Researchers describe some of their experiences of panic attacks:

I avoided going out except when it was absolutely necessary.

It's like drowning. An invisible force takes hold of you and drags you down, and you can't get away from it because you can't see it in the first place.

When out, I was prone to jumping when I encountered someone unexpectedly.

I didn't know what to say in conversation...if the conversation left predictable topics my heart would race...I would stammer and talk in monosyllables.

When I panic, I can't think, everything becomes a wall which is shouting at me. I want to run but at the same time I'm frozen in place.

If I had a conversation or meeting that I couldn't avoid and didn't want, I became very tense.

These experiences highlight some of the more debilitating symptoms of anxiety and its most extreme manifestation - panic.

When somebody is anxious or panicking, several of the following symptoms usually occur, and they may involve different parts of the body¹:

• General - sweating, hot flushes or cold chills.
• Heart - pounding heart, increased heart rate.
• Lungs - difficulty breathing or feeling of choking, chest pain or discomfort, hyperventilation.
• Abdomen - difficulty swallowing, nausea or abdominal distress.
• Arms and legs - numbness or tingling sensations, muscle tension with associated aches and pains.
• Psychological - feeling 'keyed up' or on edge, fatigue, mind going blank, difficulty sleeping.

All of the anxiety disorders have these symptoms in common. As we'll see, however, they can occur under different circumstances.

	Types of Anxiety Disorder

The 'purest' anxiety disorder is known as generalised anxiety disorder (GAD). This is characterised by out-of-control stress and worry over many aspects of the individual's life. The anxiety can be 'free-floating', which means that it isn’t connected to any particular situation. It is chronic and low grade, although it can occasionally flare. People with GAD primarily have problems with sleeplessness, fatigue, muscle tension and headaches.

Panic disorder is slightly different in that sometimes, for no apparent reason, the affected individual will have a full-blown panic attack, including many of the symptoms mentioned above. In between attacks, the individual will be anxiety-free, but over time they can (understandably) develop continuing anxiety about when the next attack will occur.

Phobias are anxiety disorders which are brought on by specific, identifiable situations. When in the situation, anxiety will lead to the individual trying to escape it by any means possible.

Obsessive compulsive disorder consists, as its name suggests, of unpleasant and distressing obsessive thoughts linked to the individual's compelling need to perform particular actions to compensate for them in some way. An example of an obsession might be the recurring thought that something horrible has happened to a loved one, a compensating compulsion might be checking that the oven is off every five minutes. Failing to act on the compulsion results in extreme anxiety of the sort outlined above.

Post-traumatic stress disorder, or PTSD, is similar to GAD but occurs after an identifiable stressor (such as war, child abuse, or a traffic accident). The individual can have flashbacks to the event in question, but why some individuals develop this after trauma and others don't is unknown.

Unfortunately, the situation is seldom as clear-cut as the above syndromes suggest. Each disorder can co-exist with any of the others – GAD for instance often co-exists with social phobia and/or other phobias.

Where anxiety is present, depression is seldom far behind.

	What Causes Anxiety Disorders?

The amygdala is the part of the brain that is thought to mediate anxiety. Stimulating the brain around the amygdala causes prolonged and serious feelings of fear, and people with anxiety disorders may have abnormal brain signalling around this area. To a certain extent, these problems appear to be inherited – anxiety disorders are significantly more common in first-degree relatives of people who have already been diagnosed with such a problem. Which neurotransmitters are involved and how, unfortunately, is still unknown.

Some researchers have speculated about whether abnormal parent-child attachments (particularly overprotective parents) can be a factor in early childhood.

	Other Causes for Anxiety Symptoms

People with anxiety, particularly chronic low-grade anxiety, will often seek a doctor's help for the physical side effects of their disorder. It is important for the doctor to ensure that there are no physical problems that could be causing the symptoms. Equally, substances such as caffeine, alcohol, cocaine and speed (and some prescription medications, including asthma inhalers) can cause anxiety symptoms as well.

	How is it Treated?

The usual response of friends and family to someone undergoing anxiety is a sense of helplessness or confusion. Sometimes they tell the affected person to 'pull themselves together'. This very seldom works. Most people with anxiety disorders know perfectly well that their fear is irrational, but that doesn't take the fear and anxiety away. In fact, knowing there's no reason to be anxious engenders a feeling of frustration and helplessness.

People often attempt to treat themselves with quick fixes such as alcohol and marijuana, which don't do anything to relieve the underlying anxiety (and can create health-related and legal problems of their own). Doctors can prescribe benzodiazepines such as diazepam (commonly known as Valium), which are very effective, but they can be addictive, have side effects, and again don't do much for the underlying problem.

The racing heart, shortness of breath and other symptoms of a body perpetually undergoing a 'fight or flight' response can be relieved slightly by beta-blockers - medications which are usually used to reduce blood pressure and prevent heart attacks and heart failure.

A more effective long-term solution is a selective serotonin reuptake inhibitor (SSRI), which have more traditionally been used as antidepressants. The best-known drug of this type is Prozac. These take a few weeks to work, but improve symptoms quite effectively. As with the other chemical options, it masks rather than cures the symptoms.

Cognitive behavioural therapy is a type of psychotherapy which can help the patient to identify anxiety-forming thoughts and consciously put a stop to them. It also teaches coping strategies for dealing with the anxiety when it occurs.

Simple relaxation exercises have been tested in trials, but these don't appear to have a large effect in the general population of sufferers. However, many people have had good results from practising them and they are side effect-free. Mindfulness techniques can also be used.

	Some Useful Links

• The Anxiety Disorders Association of America.