Long-Term Effects of Taking Tylenol PM
Pain relievers with diphenhydramine are generally considered safe for adults under 65.
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But they can be harmful when taken regularly, for the following reasons.
1. It May Mask an Underlying Sleep Problem
It’s not uncommon to have sleep struggles here or there, but needing a medication like Tylenol PM to fall asleep every night could mean that you have an underlying problem that isn’t being addressed.
“To improve sleep, it’s important to know why falling asleep or staying asleep is difficult, because the treatment options are specific to the cause,” Podgurecki says.
Common culprits include pain, anxiety, depression, restless legs, sleep apnea, shift work disorder, chronic insomnia, and poor sleep hygiene.
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Whatever the cause, it’s worth a discussion with your doctor to better understand your treatment options.
Tylenol PM can also be the cause of sleep problems, because the medication may suppress REM sleep, leading to further sleep deprivation.
2. It Can Become Less Effective Over Time
The body quickly develops a tolerance to medications like Tylenol PM.
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Before long, you may find that the dose that originally helped you fall asleep is no longer doing the trick.
“Quality of sleep becomes worse, and the person may have grogginess the next day,” says Podgurecki. “And in some people, it can paradoxically stimulate the central nervous system, which can result in difficulty sleeping.”
3. It Can Lead to Liver Damage
Consistent, long-term use of acetaminophen can be harmful to your liver.
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That’s especially true if you also drink heavily.
“There’s an increased risk of acute liver damage with taking chronic high doses if someone consumes more than three alcoholic drinks per day,” says Podgurecki.
Mixing sleep aids like Tylenol PM with alcohol or other sedatives can also increase the risk of overdosing and death.
4. You May Experience Insomnia or Withdrawal When You Stop Taking It
Once your body gets used to a nightly dose of Tylenol PM, abruptly stopping can cause problems. You may experience rebound insomnia, in which your sleep difficulties come back worse than before.
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You may also experience symptoms of withdrawal.
“Abrupt cessation of high doses can cause acute withdrawal symptoms manifested by high fever, hypertension, and bowel and bladder incontinence,” Podgurecki says.
