Sleep and substances

Sleep and Caffeine: Caffeine, the Dream & Nightmare
Ever relied on a strong cup of coffee to kickstart your morning? While caffeine can offer an energy boost, it becomes less helpful when you're trying to drift off to sleep. What many don't realise is that caffeine takes quite a while to break down in your body and can linger for more than six hours. As a result, having caffeine affects your sleep. However, you can reduce its impact by keeping an eye on your consumption and the timing of your caffeine intake.
By understanding the intriguing relationship between sleep and caffeine, you can make informed choices and take control of your rest.
So, what exactly is caffeine? It’s a natural substance extracted from coffee beans, tea leaves, and cocoa beans. As a powerful stimulant, caffeine boosts your alertness and helps you stay awake and focused when you need that extra push. However, when it comes to sleep, caffeine poses some challenges. By blocking adenosine, a compound responsible for sleepiness, caffeine stimulates your central nervous system, leading to heightened alertness and an energy surge.

But how long does caffeine's effects actually last?

How does it affect sleep quality?

For your first caffeinated beverage of the day, our Alcohol and Drug clinician suggests that you wait 2-3 hours after you wake up before having that morning coffee. This allows your body's cortisol levels to even out and can help prevent afternoon fatigue. As you can see above, the window to have your first and last caffeinated beverage is quite small!   

Not only does it make it harder to fall asleep, but it also impacts the quantity and quality of your slumber. Consuming caffeine six hours before bedtime can reduce your total sleep time by an hour!

To manage caffeine's sleep influence, limit your caffeine intake to around 300-400 mg per day. This varies depending on which caffeinated beverage you have:

Sleep and Alcohol: Alcohol’s Sleep Trickery  

If you’ve ever had a bit too much to drink on a Wednesday night at Bar101, you know that alcohol may help you doze off faster. However, alcohol often results in lighter sleep and overall reduced sleep quality. Especially if you’ve been out partying till the early morning, alcohol restricts you from getting enough sleep to feel rested and alert throughout the day.   

How does it affect sleep quality?

Even if you drink a low intake, alcohol reduces the quality of sleep from the get-go. Alcohol reduces sleep onset latency, which can cause significant sleep disruptions in the later half of your sleep. Moderate to high doses of alcohol (so more than two standard drinks) can reduce the total amount of REM (Rapid Eye Movement) in your sleep, which is needed to feel well rested and awake the following day. Drinking before bed often can cause you to experience insomnia symptoms and feel extremely sleepy the following day, which can make it hard to concentrate on work and study. To manage alcohol’s sleep influence, limit your intake to no more than two standard drinks in a day.  

Sleep and other Drugs: High on Sleep

We’re all aware that when we’ve got a headache or any sort of pain, it’s normal to take a pill, usually paracetamol, to alleviate the symptoms. While drugs work in favour for some areas, drugs and sleep have a complicated relationship, and the type of drug or substance you consume may impact your sleep in different ways. By understanding the interesting relationship between sleep and other substances, you can make informed choices and take control of your rest.  

How do sleeping pills affect sleep quality? 

It is common that for people who may be struggling with sleep and insomnia, that healthcare professionals recommend sleeping medication. However, sleeping pills are only usually considered when other avenues, such as sleep hygiene practices and therapy, are no longer successful. Sleeping pills may be effective for you in the short-term to get your sleep cycle back on track, but it may not be helpful for you when used in the long-term. 

Melatonin can help you fall asleep for about 8 to 20 minutes faster, but also adds less than 35 minutes to your nightly sleep. If you are taking melatonin pills, it may not be effective if you are also consuming alcohol, caffeine, tobacco, or any other prescribed medications.

How does weed affect sleep quality?  

There is often an assumption that cannabis use can help you fall asleep. This may be true for infrequent and short-term cannabis use, but it is generally not recommended as a sleeping aid on a long-term basis as this can impact your sleep quality.   Frequent cannabis use leads to more difficulty with sleeping, whether that be waking up early and not being able to fall asleep again, difficulty falling asleep, or experiencing consistent sleep disturbances. Long-term cannabis use generally causes some people to develop a tolerance to its sedative effects. The higher your tolerance is, the more likely you are to take more weed to obtain the same high. With heavy cannabis use that is frequent and on a long-term basis, this can create impaired memory and daytime sleepiness the following day. You may even feel paranoid or anxious when taking weed, which can also create further sleep disturbances.   It's important as well that if you are taking weed, in any form or shape, that you keep an eye out for synthetic cannabinoids. Synthetic cannabinoids can make you feel extra drowsy, dizzy, groggy, panicked, and even unable to maintain consciousness (also known as ‘dropping’) which can impact your sleep quality and quantity significantly. To learn more on how to safely use cannabinoids, read here.

How does nicotine (and similar substances) affect sleep quality?

Vapes are everywhere these days, but do you know how it might impact your sleep? Generally, people don’t realise how nicotine, tobacco, and vaping products with nicotine impacts sleep quality and quantity.   Let’s look at nicotine, specifically. Nicotine is a stimulant, like alcohol, and releases neurotransmitters (i.e., serotonin) that is associated with pleasurable feelings. However, frequent smoking and vaping can create inconsistent levels of these neurotransmitters in your brain, which means you’ll spend more time awake in bed and have a harder time falling asleep, as well as less time spent in a deep and restorative sleep. Because of this, you might find it’s harder to get up in the mornings or experience daytime sleepiness and insomnia-like symptoms more frequently. Heavy smoking use can also be especially troublesome if you have respiratory conditions, such as asthma, as smoking can exacerbate respiratory problems and cause frequent sleep disturbances.   Substances like nangs (NOS or nitrous oxide), for instance, do not have any direct impacts on your sleep and are not as harmful when compared to other drug and substances. However, it is important to consider the context in which if you are mixing different substances, these interactions could impact your sleep quality and quantity further. If you’d like to know more about how certain drugs may impact your sleep, check out The Level here.

If you experience issues with substances and sleep, please contact our Alcohol and Drug Clinician Niamh Pritchard:


Alcohol and sleep – effects on normal sleep  

Does Alcohol Affect my Sleep? – Sleep Seeker Co. 

Sleep – how food & drink affects | Healthify