Sleep is a problem when you have trouble sleeping at night. You may find it difficult to sleep or you may wake up several times during the night.

Difficulty sleeping can affect your physical and mental health. Lack of sleep can also cause frequent headaches or difficulty concentrating.

Most people have trouble sleeping at some point in their lives. Some people may feel renewed after only six or seven hours of sleep. However, most adults need about eight to eight hours of sleep each night to feel comfortable.

Symptoms of difficulty sleeping in the day include frequent concentration in the day, frequent headaches, irritability, daytime fatigue, waking up too early, waking at night or taking several hours to sleep.

You can also experience a little bit of energy during the day, or dark circles under the eyes.

What Causes Sleep Disorders?
In the elderly.
There are many possible causes of insomnia, including your sleep habits, lifestyle choices and medical conditions. Some reasons are minor and may be better than self-care, while others may require you to seek medical attention.

Causes of insomnia can include aging before bed, excessive stimulation (such as watching television, playing video games or exercising), excessive caffeine, noise disturbances, uncomfortable bedrooms or feelings of anxiety.

Excessive sleep in the day, exposure to sunlight, frequent urination, physical pain, lack of time, and some prescription medications can also cause sleep problems.

For many people, stress, anxiety, depression or work schedules can also affect their sleep. For others, sleep disturbances are caused by sleep disorders, such as insomnia, sleep disorders and restless leg syndrome.

In infants.
Insomnia can also occur in children. It is normal for newborns to wake up several times during the night. However, most babies will start sleeping all night after 6 months.

If an older child shows signs of insomnia, it may be a sign that she has been bitten, sick, hungry or upset by gas or digestive problems.