How Is Insomnia Diagnosed?

Usually, your doctor will diagnose insomnia based on your medical and sleep histories and a physical exam. He or she also may recommend a sleep study. For example, you may have a sleep study if the cause of your insomnia is unclear.

Medical History

To find out what's causing your insomnia, your doctor may ask whether you:

• Have any new or ongoing health problems
• Have painful injuries or health conditions, such as arthritis
• Take any medicines, either over-the-counter or prescription
• Have symptoms or a history of depression, anxiety, or psychosis
• Are coping with any very stressful life events, such as divorce or death

Your doctor also may ask questions about your work and leisure habits. For example, he or she may ask about your work and exercise routines; your use of caffeine, tobacco, and alcohol; and your long-distance travel history. Your answers may give clues about what's causing your insomnia.

Your doctor also may ask whether you have any new or ongoing work or personal problems or other stresses in your life. Also, he or she may ask whether you have other family members who have sleep problems.

Sleep History

To get a better sense of your sleep problem, your doctor will ask you details about your sleep habits. Before your visit, think about how to describe your problems, including:

• How often you have trouble sleeping and how long you've had the problem
• When you go to bed and get up on workdays and days off
• How long it takes you to fall asleep, how often you wake up at night, and how long it takes to fall back asleep
• Whether you snore loudly and often or wake up gasping or feeling out of breath
• How refreshed you feel when you wake up, and how tired you feel during the day
• How often you doze off or have trouble staying awake during routine tasks, especially driving

To find out what's causing or worsening your insomnia, your doctor also may ask you:

• Whether you worry about falling asleep, staying asleep, or getting enough sleep
• What you eat or drink, and whether you take medicines before going to bed
• What routine you follow before going to bed
• What the noise level, lighting, and temperature are like where you sleep
• What distractions, such as a TV or computer, are in your bedroom

To help your doctor, consider keeping a sleep diary for 1 or 2 weeks. Write down when you go to sleep, wake up, and take naps. (For example, you might note: Went to bed at 10 a.m.; woke up at 3 a.m. and couldn't fall back asleep; napped after work for 2 hours.)

Also write down how much you sleep each night, as well as how sleepy you feel at various times during the day.

You can find a sample sleep diary in the National Heart, Lung, and Blood Institute's "Your Guide to Healthy Sleep."

Physical Exam

Your doctor will do a physical exam to rule out other medical problems that might cause insomnia. You also may need blood tests to check for thyroid problems or other conditions that can cause sleep problems.

Sleep Study

Your doctor may recommend a sleep study called a polysomnogram (PSG) if he or she thinks an underlying sleep disorder is causing your insomnia.

A PSG usually is done while you stay overnight at a sleep center. A PSG records brain electrical activity, eye movements, heart rate, breathing, muscle activity, blood pressure, and blood oxygen levels.