Impact of drugs on sleep

• Caffeine is a stimulant drug which means it can make it much more difficult to fall asleep if ingested.
• Caffeine affects sleep due to its effect on adenosine. Caffeine blocks adenosine receptors and therefore makes the body less reactive to adenosine build-up which will stop us feeling tired.
• Caffeine also causes the pituitary gland to secrete hormones that cause the adrenal glands to produce adrenalin. This will increase your attention level and give you an extra burst of energy. This explains why people drink coffee if they have had to wake up very early in the morning.
• People should be mindful of their consumption of caffeine, particularly later on in the day as there is a clear impact on our biological processes involved in sleep. However, there are clear individual differences on the impact of caffeine on sleep. Some people can’t drink a coffee after 12pm, others can drink coffee at 8pm and still fall asleep relatively easily.
• Drake and others assessed the impact on sleep of caffeine consumption at different times of day, suggesting that caffeine consumed up to 6 hours before sleep may have disruptive effects on sleep.
• Pollak

  191 students kept a daily diary for 2 weeks. Researchers found that a higher caffeine intake was associated with shorter nocturnal sleep duration, increased sleep disruption and increased daytime sleep.
• A study of 15,000 American high school students found that reports of feeling tired in the morning and having difficulty sleeping was experienced more commonly in those adolescents that had a high intake of caffeine.
• Clark found that “Caffeine typically prolonged sleep latency, reduced total sleep time and sleep efficiency, and worsened perceived sleep quality. Slow-wave sleep and electroencephalographic (EEG) slow-wave activity were typically reduced, whereas stage 1, wakefulness, and arousals were increased.”
• Alcohol is a soporific which means it encourages sleep. However, the quality of that individual's sleep under the influence of alcohol will be compromised. After drinking alcohol, production of adenosine is increased, allowing for a fast onset of sleep. But it subsides as quickly as it came, making you more likely to wake up before you’re truly rested.
• Furthermore, another reason why people get lower-quality sleep after drinking alcohol is it reduces the amount of REM sleep an individual will have. REM is considered the most restorative type of sleep, and therefore can explain why the following morning you may wake up feeling groggy, unfocused and generally ‘rough.’
• People who drink alcohol regularly should reduce their intake in order to observe positive effects on their sleep.
• Sleep researchers should ensure that participants have not had any alcohol prior to studying sleep as this can have an impact on their results.
• Toehrs and Roth Found that alcohol use improved sleep in non-alcoholics but tolerance to its effects on sleep quickly developed. In alcoholics sleep disturbance is common and alcohol exacerbates daytime sleeping and sleep-disordered breathing.
• William and Salamy gave participants alcohol 30-60 minutes before bedtime but allowed them to choose between 1-6 drinks. Results found that participants who drank more alcohol fell asleep faster, however they woke more frequently and suffered from more disturbed sleep.