Caffeine insomnia (caffeine-induced sleep disorder) is a disorder caused by the overconsumption of caffeine.
Caffeine is the most consumed psychoactive substance (a substance that stimulates the central nervous system) and , therefore, may be considered a drug. It was estimated that about 80% of the world’s population consume caffeine every day.
Caffeine is so popular, because of its ability to alleviate fatigue, increase the feeling of wakefulness and improve concentration and focusing.
Difficulties to fall asleep were reported as one of the most spread side effects of caffeine consumption, although in some cases it is supposed to be a benefit of caffeine.
Caffeine intake may be related to the sleep quality and daytime sleepiness.
Caffeine is known as an adenosine receptor antagonist. Adenosine is supposed to be responsible for the feeling of sleepiness and fatigue. Caffeine binds tge A1 and A2a adenosine receptors and i.e. reduce the tiredness and sleepiness. However, recent studies suggest that the wakefullness induced by the caffeine depends on adenosine A2a receptors.
In the brain caffeine can increase the secretion of norepunephrine causing the response kniwn as “fight or flight” response.
Caffeine interferes with a normal pattern of sleep when consumed in a great amounts. Researchers suggest that caffeine increases sleep latency (the time to sleep) and reduces sleep duration, especially if the amount of ingested caffeine is more than 210 mg for a 70-kg person before the usual bedtime. However, usually people don’t consume caffeine in such amounts.
The way the caffeine affects the sleep pattern is different in every person and usually correlates with the amount of caffeine consumed by the person every day, i.e. high consumers of caffeine usually don’t experience any sleep disturbances, whereas those who consume caffeine rarely are more likely to face difficulties while falling asleep.
However, the consumption of large amounts of caffeine insomnia (more than 3 mg/kg in a single beverage) will definetely affect the sleep duration and prevent the person from falling asleep. The consumption of caffeine at such dose may not only cause insomnia, but also lead to the caffeine insomnia intoxication characterized by the agitation, restlessness and excitement.
It was estimated that the consumption of caffeine at doses of 300-400 mg before going to bed leads to 30-80 minute reduction of total sleep time.
Depending on the time of caffeine ingestion sleep-onset or middle-of-night insomnia may be caused. It was suggested that caffeine may affect the sleep quality as well as increase the the light sleep and shorten the deep sleep. It seems that REM (rapid eye movement) sleep is less affected than slow-wave sleep.
Probably, not only the caffeine consumed in the evening may affect the sleep, but also the whole caffeine ingested during the day may change the sleep pattern.
The diagnosis of caffeine-induced sleep disorder is made based on the evidences of the physiological effects of caffeine (according to the examination) and the disorder is not related to to narcolepsy, mental disorder or a circadian rhythm disorder.
If a person experiences sleep difficulties related to caffeine insomnia he/she should stop the consumption of caffeine.
To sleep better a person should:
– create a regular sleep-wake rhythm;
– establish some routine activities before going to bed;
– organize a comfortable, dark and cool room;
– have a comfortable bed and pillows;
– not eat at least 3-4 hours before going to bed;
– not consume any caffeine-containing beverages or foods;
– have a walk before going to sleep;
– not work in the bed;
– try using decaffeinated beverages;