Your daughter has a medical problem called insomnia, which literally means not getting enough sleep.  There are many reasons for insomnia, some are obvious while others require detailed questions and tests.  Since she has the problem for two years already, you don’t expect her to get completely better overnight.

Insomnia can be differentiated according to the time when the person has difficulty sleeping.  Some have difficulty falling asleep, but once they do, they can sleep through the night.  Some can fall asleep, but wake up once or more times through the night, and have difficulty getting back to sleep.  Yet others can fall asleep, but wake up much earlier in the morning than needed.  Your daughter seems to have two of the three situations here.

Insomnia is not an uncommon medical problem.  It has been estimated that 10 to 20% of adults suffer from chronic insomnia, which affects their daytime functioning.  This is especially true in seniors, but we have also seen many teenagers with this medical condition.

There has been much research in the last few decades trying to understand the physiology of sleep, and in doing so, probe into the reason for those who suffer from insomnia.  You may have heard of the term REM sleep.  REM means rapid eye movement, a period of sleep when we usually have rather vivid dreams.

When we fall asleep, we go through a period called non-REM sleep which lasts 45 to 60 minutes before entering REM sleep.  Then, through the night, we often alternate between REM and non-REM sleep.  The duration of each changes with age, but we still don’t fully understand many aspects of sleep.

What we know is that our brain has a sleep-awake cycle that is controlled by a series of brain cells located in several centres deep inside our brain.  A growing number of brain chemicals have been discovered which are important in regulating this sleep-awake cycle.  These brain cells and chemicals are also affected by, and in turn will influence, many other hormones and chemicals in the body.  That is the reason why not getting enough sleep can affect a person in many ways.

Many people recognize that they have difficulty sleeping if they have to travel, especially if they fly to a place which has a time-zone several hours different from their home.  The duration of sitting on the plane, as well as the different time zone at the destination, make it difficult for some to fall asleep at their usual bedtime.  It often takes a few days for many to adjust to this change.  Some have difficulty sleeping in a different bed or with different pillows.  Those who have to work day and night shifts find it very difficult, if not impossible, to adapt to this changing sleep-awake cycle.

Psychological trauma, like the loss of a loved one, can cause acute insomnia.  It can go on for weeks, and sometimes months.  Sometimes this can happen even when a close friend moves away.  It is important to recognize this trigger in anyone with sleep disturbance.

For some, consumption of excessive caffeine (including coffee, tea, and soft drinks), especially in the evening, can affect sleep.  Although some believe that drinking alcohol or smoking can calm the nerves, both can disturb sleep instead of helping it.

Many teenagers have poor sleeping habit which makes it difficult for them to fall asleep or sleep through the night.  Some engage in highly stimulating activities late into the evening, like watching television, playing computer games, or chatting with friends online or on the phone, or texting.  They may claim that these activities calm them down, but the reality is that their brain gets over-stimulated so that it is difficult for them to fall asleep.  Many teenagers stay up well pass midnight, and then cannot get up in the morning to go to school.  If you suspect that she is using her smartphone or tablets at night, remove them to your room before she goes to bed.

There are also other medical conditions that can cause insomnia.  An overactive thyroid gland producing too much thyroid hormone can affect sleep, as well as many other symptoms of excessive thyroid hormone.  Some children with asthma have more difficulty breathing or coughing at night.  Those with stomach reflux problem can be woken up at night because of their reflux.  Drinking too much fluid in the evening can affect sleep because of the full bladder.

Sleep apnea is a medical condition that deserves special discussion.  This is caused by blockage of the upper airway.  In children, the most common cause is enlargement of the adenoid, a patch of lymphatic tissue behind the nose.  These children snores at night and have periods where they stop breathing, wakening them through the night so that they are still tired in the morning.

There are many psychiatric conditions that can affect a person’s sleep.  The most common ones are anxiety and depression.  The mind cannot stop thinking and they can’t fall asleep or they wake up through the night.

As you can see, insomnia is a complex medical problem that have many causes, some may be obvious while others require detailed questioning as well as tests.  Treatment depends on the cause of problem.  Sometimes medicine may be necessary for a short time to help a person while dealing with the cause of insomnia.