Cannabis’s effects on sleep and sleepiness can also be influenced by how you take it, said Dr. Ashima Sahni, a pulmonologist and sleep specialist at the University of Illinois College of Medicine. Oral forms, like pills or edibles, will take longer to kick in than inhaled forms, she said, but their effects on sleep will last longer throughout the night. Inhaled cannabis, via vaping or smoking, will yield faster results, but they won’t last as long. Of course, Dr. Sahni added, vaping and smoking can come with certain health concerns including damage to the lungs and inflamed airways.
There is also some evidence that cannabis might indirectly help with sleep by alleviating chronic pain and anxiety — the two top concerns motivating new patients to try medical cannabis, said Rahim Dhalla, a pharmacist specializing in medical cannabis in Ottawa, Canada, who has studied patient experiences with cannabis for sleep. Though research in this area is “limited” and “the data are kind of all over the place,” Dr. Kaufmann said.
What to consider before trying cannabis for sleep
In her clinical experience, Dr. Bidwell said that people who use cannabis products for sleep seem to be the most satisfied with them when they use them every now and then but not every day. This is because using THC too frequently can lead to a tolerance or dependency, she said, which can reverse the benefits of cannabis on sleep.
“As you start taking it more chronically, you fall into this trap that, for the same amount of effect, you have to go up in the quantity,” Dr. Sahni added. And eventually, you might get to a point where it doesn’t work at all.
At the same time, you might become so dependent on it that you have to keep taking it to stave off withdrawal symptoms. In such people with marijuana addictions, Dr. Bidwell said, stopping its use can result in symptoms like anxiety, irritability, nausea and even unsettling dreams that can disrupt sleep. “That’s one of the main reasons they go back to using it, or why they can’t fully quit,” she said, “because of how hard it is to sleep as part of that withdrawal.”
And some people who use too much THC can report a “weed hangover” the next morning, which can include symptoms like fatigue, headache and dry eyes and mouth. Using CBD, however, does not seem to lead to a tolerance or dependency.
In Dr. Kaufmann’s clinical experience, many of her patients want to try cannabis for sleep because they are wary of sleep medications. But she urges them to try some lifestyle strategies first: such as going to bed and waking up at the same times every day, reducing screen-time before bed, cutting out afternoon caffeine, getting daily exercise and keeping your bedroom cool, clean and comfortable.
