Although most people associate the term insomnia with endless nights lying awake staring into the gloom, waiting to drop off, it is actually a catch-all term used to describe a wide variety of symptoms with varying degrees of severity and covering problems such as staying asleep or waking up too early in the morning.
Each of these disorders requires a different type of treatment, and determining whether or not you are suffering from primary or secondary insomnia is the first step to receiving the appropriate one.
Primary insomnia is classified as disturbance to sleep patterns lasting at least a month and has no obvious physical or medical cause.
Secondary insomnia is a side effect of a separate complaint, such as asthma (which can worsen at night, causing sleeplessness) or depression.
Causes for the insomnia are classified as intrinsic (a condition within the body, such as sleep apnoea, narcolepsy or Restless Leg Syndrome) or extrinsic (such as alcohol-disturbed sleep, a noisy sleeping environment or an emotional complaint, such as stress or grief).
And the length is also key in deciding how serious your problem is: transient insomnia is a disturbance in sleeping patterns that lasts for a few nights, brought on by factors such as jet lag, excitement, stress, illness or a change in sleep schedule.
Intermittent insomnia persists for about two to three weeks, and can be caused by a job change, serious illness or financial problems.
Chronic insomnia lasts longer than a few weeks and seems to show no signs of abating naturally; perhaps the cause in unclear.
When trying to treat insomnia, you need first to understand which of the categories your symptoms fall into; this will then help you to find the key to restoring restful sleep.
A good way to work out the cause of your poor sleep is to keep a sleep diary, to help pinpoint any recurring themes.
If you can track a pattern, such as deadlines and late dinners directly affecting your ability to drop off, you can start by eliminating them, or managing them differently; in some cases, simply moving the TV out of the bedroom can have startlingly effective results.
However, self help measures may not bring you any real relief.
It may be that you are suffering from a condition called psychophysiological insomnia, which describes 'learnt' insomnia.
A period of sleeplessness may have been triggered by grief or stress, and can persist long after the negative even had been dealt with.
Or the sleeper can have become anxious about sleeping well, making it a source or stress and stimulus in itself.
Idiopathic insomnia describes a lifelong sleeplessness that is usually attributed to an abnormality in the neurological or neurochemical control of the sleep-wake cycle, and usually makes itself known from childhood.
There is also sleep state misperception, where a patient imagines they have slept much less than they actually have, but this can still leave them feeling dreadful and distressed.
Even if you need to approach a healthcare practitioner to address the problem, the diary will be invaluable in finding a treatment to fulfil your specific needs.
It will also help ease the feelings of helplessness and frustration that so often accompany insomnia.