Study shows common drugs affect sleep

30 Jun 2021

We all know that an afternoon coffee can make it harder for us to get to sleep, while consuming alcohol may help us fall asleep a little quicker. But what are the effects of these psychoactive drugs, those that alter our consciousness, mood and thoughts, on our actual sleeping patterns and physical and mental health?

mug on table in bedroom

With one in five women reportedly getting less than six hours of sleep a night, little is known about the potential role these substances play in assessing and diagnosing sleep disorders. Now, a recent study by researchers from Turning Point, Monash University and Eastern Health has found that consuming these drugs in high quantities can be harmful, leading to stress, burnout and an inability to function properly.

An overnight sleep study in a hospital sleep clinic involving 120 patients investigated the prevalence of commonly used psychoactive drugs, including alcohol, caffeine and other medications, and the relationship between use and sleep and performance outcomes.

Caffeine was the most common drug used among patients, with almost 15 percent consuming it in high quantities (more than four cups of coffee a day), resulting in a reduction in excessive sleepiness. While moderate caffeine intake can be beneficial in keeping us alert, regular consumption in high doses can lead to poor physical and mental health outcomes including anxiety, agitation and headaches.

Dr Rowan Ogeil who led the study said it provided an important snapshot of how different drugs affect sleep.

“We see this as an important reminder for people with a sleep disorder or undergoing a sleep assessment to discuss their use of drugs and medications with their doctor and hospital staff,” Dr Ogeil said.

The study also revealed an association between patients who drank at harmful levels and an increase in reporting of near miss motor vehicle accidents. Alcohol is not an effective sleep-aid as it disrupts both the overall quality of sleep and underlying sleep architecture resulting in adverse effects on our wellbeing, memory and next-day performance. This is particularly concerning given a Sleep Health Foundation Survey showed that more than 10 percent of Australians were consuming alcohol at least a few nights every week to overcome insomnia.

"Many people are led to believe that alcohol helps you sleep because it makes you feel more relaxed. However, alcohol actually has negative effects on your sleep quality, and causes restless sleep particularly in the second half of the night."

Most notably in the study was the presence of polypharmacy (use of at least five medications) amongst participants with two or more medical conditions. Prescription and non-prescription drugs can affect sleep quality, by either promoting sleep or helping us to stay awake. Given sleep quality is important for recovery following illness or injury, the findings highlight the importance of discussing with patients the potential side effects of these medications.

“Sleep is vital to our everyday functioning and mood, any change in the time you spend sleeping, or the quality of sleep that you get should be discussed with your doctor, including when you start any new medication,” said Dr Ogeil.