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Can Tylenol (Acetaminophen) Cause Insomnia?

by Dale Cudmore | Updated: Jan 11, 2023

Tylenol is just the most popular brand name for the drug acetaminophen.

Some people believe that Tylenol can improve sleep, even though research shows that it is generally associated with insomnia (1).

It’s understandable why some people might think acetaminophen is good for sleep. It’s often taken to address aches and cold symptoms, and by treating those symptoms successfully, sleep will of course be improved at the time (2).

Let’s go over all the relevant research I could find and uncover the truth.

Research About Acetaminophen and Sleep

One study looked at the effects of 3 common over the counter medications on sleep quality: acetaminophen, aspirin, and ibuprofen (3). All of them were compared to a placebo group.

There were no statistically significant differences in sleep quality in the acetaminophen group. Even though sleep efficiency was lower, and number of awakenings were higher, they did not reach statistical significance (indicated by an asterisk in the chart below).

There were only 9 subjects in each group, so perhaps with a bigger sample size there would have been a significant difference. As an aside, both aspirin and ibuprofen significantly lowered sleep efficiency and at least one other metric of sleep quality.

So maybe we just need more data, let’s move on...

  • In a study of acetaminophen in elderly people with sleep problems (which are fairly common), there was no significant difference in sleep efficiency or insomnia severity score, for better or worse (4).
  • Women often take Tylenol during menstruations, and period insomnia is common, which makes it a great population to study for this topic. While Tylenol helps with symptoms like cramping, one study found that once again acetaminophen had no effect on body temperature or sleep architecture (5).
  • Finally, one study in post op patients found that acetaminophen improved sleep quality in patients that were in mild or moderate pain, which suggests that the benefits of reducing pain outweigh any potential negative effects on sleep (6).

SummaryThere’s no clear evidence showing that acetaminophen has a reliable negative effect on sleep. If it does, it’s likely a small effect, and not enough to cause insomnia symptoms on its own.

Other Situations Where Tylenol May Affect Sleep

There are 3 major areas of concern when it comes to side effects of Tylenol:

  • Allergic reactions
  • Interactions with other drugs
  • Liver damage

For an over the counter drug, Tylenol can be quite dangerous if enough is taken, or it is used on a regular basis.

SummaryAny sort of negative reaction from Tylenol could cause sleep issues among other health problems.

Summary: Does Tylenol Cause Insomnia in Some People?

If someone has a headache or some other pain that can interfere with sleep, there’s evidence that Tylenol can actually improve sleep quality.

For everyone else, the research we looked at shows that Tylenol typically has either no effect, or a small negative effect on sleep when taken in safe amounts. However, there will always be exceptions, and more research may reveal a clearer impact on sleep in certain populations.

Finally, Tylenol can cause sleep issues if it’s misused to the point that it causes other health problems. Even though it’s an over the counter drug, Tylenol use should be supervised by a doctor if there’s any doubt in using it properly, as it can be quite dangerous.


  1. Treatment options for Insomnia
  2. Pharmacotherapy of Insomnia in Children
  3. Nonsteroidal anti-inflammatory drugs affect normal sleep patterns in humans
  4. Acetaminophen for self-reported sleep problems in an elderly population
  5. Acetaminophen does not affect 24-h body temperature or sleep in the luteal phase of the menstrual cycle
  6. Effects of doxylamine and acetaminophen on postoperative sleep

Medical Disclaimer: The information on is not intended to be a substitute for physician or other qualified care. We simply aim to inform people struggling with sleep issues about the nature of their condition and/or prescribed treatment.

About the authorDale is the founder of Snooze University and a sleep researcher. I overcame my sleep issues and now I'd like to help you do the same by summarizing the latest sleep studies for you.