In the sleep laboratory it is shown that REM sleep occupies about 25 per cent of the time spent in sleep. When a person takes sleeping pills, REM sleep is reduced to 5 or 10 per cent of sleep time, but if the pills are continued for many days the REM component gradually returns to 25 per cent However, it has been shown that if sleeping pills are suddenly stopped there is an increase in REM sleep to about 40 per cent of sleep time, and, in the following nights, more dreams and nightmares are experienced. This is because the sleep induced by drugs is not a natural sleep—it has less of a REM component. When the drugs are stopped, there is a catch up in REM sleep, and this is called ‘rebound of REM sleep’ or ‘rebound insomnia’.
Initially benzodiazepine is prescribed for the treatment of insomnia arising from stress or some other reason. When the original stress is over, and the reason for taking these pills is gone, the drugs are stopped abruptly. This is when rebound insomnia sets in. People who suffer from rebound insomnia believe that they have lost the innate ability to sleep. This rebound insomnia is only transient and lasts just a few days. If these people persevere, the rebound insomnia passes and their sleep becomes normal again. However, there may be some who become psychologically dependent on these pills, meaning their confidence to sleep has disappeared. These are the people who should find this book useful, as it will help them regain their confidence to sleep.
It has also been shown that sleeping pills stop working after two weeks. The reason is that the body develops an increasing tolerance to the pills. The same dose of sleeping pill is no longer resulting in sleep as it used to. But then why do people persist in taking them? The answer is to prevent the withdrawal symptom—rebound insomnia.