Insomnia-
is a condition characterised by unsatisfactory quantity or quality of sleep,which persists for a considerable period of time.
The normal variations from what is considered as normal(8-81/2 hrs of sleep) should not be the primary consideration in the diagnosis of insomnia,because some individuals obtain a minimal amount of sleep and do not consider themselves as insomniacs.There are individuals who suffer from poor quality of sleep.
Sleep quantity is judged subjectively and or objectively as within normal limits.
The most commom complaint is the difficulty in falling asleep followed by staying asleep and early final wakening.
Insomnia commonly develops at a time of increased life stress,tends to be more common in women,older individuals,psychologically disturbed and individuals who are socioeconomically disadvantaged.
For a diagnosis of nonorganic insomnia(nonorganic-not associated with a demonstrable change in body organs or tissue)
-They should have a complaint that is either the difficulty in falling asleep followed by staying asleep,or a poor quality of sleep.
-The sleep disturbance should have had occured at least 3 times per week for at least one month.
-Having a preoccupation with sleeplessness and excessive concern over it's consequences at night and during the day.
the unsatisfactory quantity and or quality of sleep either causes them marked distress or interferes with ordinary activities of daily living.

Insomnia is also a common symptom of other mental disorders such as affective disorders(depression and mania),eating disorders,substance misuse(use of stimulants like amphetamines,crack),schizophrenia,anxiety disorders.
Insomnia can also be due to a painful physical conditions.

Insomnia can also occur due to a disorder in the sleep-wake schedule due to a lack of synchrony between the individual's sleep-wake schedule and the desired sleep wake schedule for the environment,causing a lack of sleep or excess sleep.The causes may be psychological or may have an organic cause.Individuals who travel frequently across time zones may lead to malfunctioning of the bioloical clock.

Treatment options include prescription drugs such as-Benzodiazepine group of drugs(Diazepam,Nitrazepam,Temazepam,Flunitrazepam etc)

Non Benzodiazepine group of drugs -(Zopicone,Zolpidem etc)

Herbal remedies

Treating medical causes like Restless leg syndrome
Sleep apnea syndrome.