In some cases, the cause of insomnia cannot be determined. This is called idiopathic insomnia. People with idiopathic insomnia often have trouble falling or staying asleep their entire lives. Doctors believe it may be caused by imbalances of certain chemicals in the brain. People with idiopathic insomnia often have family members with the condition.

What are the signs and symptoms of insomnia?

Common signs and symptoms of insomnia may include difficulty falling asleep, difficulty staying asleep or waking up too early. You may wake up feeling tired, even after a full night's sleep and experience excessive daytime fatigue or sleepiness. You may suffer from an inability to concentrate, irritability, anxiety or depression. Finally, you may find that it is harder to remember things because your brain has not had adequate rest.

How is insomnia diagnosed?

It's usually easy to tell if you have insomnia, even without an official diagnosis. However, it can be more difficult to determine the cause or any related problems, such as other sleep disorders. A review of your medical history, a physical examination and details of medications and lifestyle may help pinpoint the cause of your insomnia. You may also be evaluated for psychiatric conditions or be asked to keep a sleep diary to document sleep patterns and behaviors. In some cases, you may be referred to a sleep center where sleep is analyzed by sleep disorder professionals. This is usually done to rule out other sleep disorders.