Are Sleep Pills Bad for You? What the Research Really Says

Sleep difficulties are incredibly common, and it’s no surprise that millions turn to sleep aids for relief. But are sleep pills bad for you? And if so, how? The answer depends on what kind of sleep aid is used, how often it's taken, and the underlying cause of the insomnia. This article breaks down the risks, side effects, and safe usage guidelines for sleep pills—especially over-the-counter (OTC) sleeping pills.

Understanding Sleep Aids: Prescription vs OTC

Sleep aids are generally categorised into:

• Prescription Sleeping Pills: Medications such as Zopiclone and Zolpidem are prescribed for severe insomnia and are intended for short-term use. ​

• Over-the-Counter (OTC) Sleep Aids: These often contain sedating antihistamines like diphenhydramine, commonly found in products like Nytol. 

Additionally, supplements like melatonin are sometimes used, though their availability and approval vary within the UK. 

Are OTC Sleep Aids Bad for You?

OTC sleep aids are generally considered safe for occasional use, but they come with notable downsides when used regularly:

1. Cognitive Impairment and Drowsiness

Antihistamines used in OTC sleep aids often cause next-day drowsiness, brain fog, and slower reaction times. This can be especially risky for older adults, who may already have age-related cognitive decline.

2. Tolerance and Dependence

Frequent use can lead to tolerance, where the same dose becomes less effective, leading people to increase usage. Although not physically addictive, the psychological dependence can be significant.

3. Impact on REM Sleep

Antihistamine-based sleep aids may reduce the amount of time spent in rapid eye movement (REM) sleep—the most restorative phase of the sleep cycle.

4. Liver Stress

Many OTC sleep aids are combined with painkillers (like acetaminophen) or alcohol-based syrups, both of which can place extra strain on the liver, particularly with long-term use.

Are Prescription Sleep Pills Bad for You?

Prescription sleep aids can be helpful in the short term, especially in cases of acute insomnia. However, they come with a more serious set of risks:

1. Dependency and Withdrawal

Some prescription sleep medications (especially benzodiazepines) can cause physical dependence. Stopping suddenly may lead to rebound insomnia or withdrawal symptoms.

2. Risk of Falls and Accidents

In older adults, sedative medications increase the risk of nighttime falls and injuries. This has led to updated NHS and NICE guidelines recommending limited use in older populations BNF/NICE.

3. Sleepwalking and Memory Issues

Drugs like Zolpidem have been linked to parasomnias (e.g., sleepwalking, driving while asleep) and memory lapses. These effects can be unpredictable and serious.

4. Brain Health Concerns

Long-term use of sedative-hypnotics has been associated with cognitive decline and an increased risk of dementia. While causation remains debated, several large studies have flagged significant associations:

• A 2015 study in JAMA Internal Medicine found a strong correlation between anticholinergic drug use—including diphenhydramine—and increased dementia risk in older adults Gray et al., 2015.

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• A population-based study in BMJ found that benzodiazepine use was associated with a higher risk of dementia BMJ, 2012.

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• A Korean nationwide cohort study found increased dementia risk linked to hypnotics, especially in long-term or high-dose users ScienceDirect, 2024.

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• Another population study concluded that sedative-hypnotics—particularly benzodiazepines—were associated with cognitive decline British Journal of Clinical Pharmacology.

Can Sleep Pills Affect the Liver?

Yes—particularly when taken in combination with other medications or alcohol. OTC sleep aids that include acetaminophen can be harmful to the liver if taken frequently or at high doses.

People with existing liver conditions or those taking multiple medications should consult a healthcare provider before using sleep aids.

Are Sleep Pills Bad for Your Brain?

There’s growing evidence linking long-term sleep aid use to cognitive decline. This includes both OTC antihistamines (which are anticholinergic) and prescription sedatives. These medications have been associated with memory issues and increased dementia risk.

The risks appear especially pronounced in older adults and long-term users. While short-term or occasional use is less likely to cause harm, the cumulative effect of sedative use is a growing concern in neurology and geriatrics.

Is It Safe to Take Sleeping Pills Every Night?

Most doctors advise against daily use of sleep aids—especially without identifying the root cause of the insomnia. While occasional use can be safe, nightly use increases the risk of dependency, tolerance, and side effects.

Sleep aids should ideally be a short-term solution while working on long-term strategies like cognitive behavioural therapy for insomnia (CBT-I), lifestyle changes, or addressing medical conditions that affect sleep.

Safer Alternatives to Sleep Pills

• CBT-I (Cognitive Behavioural Therapy for Insomnia): Proven to be more effective long-term than sleep medications.

• Sleep hygiene: Consistent wake-up times, limiting caffeine, screen exposure, and creating a dark, quiet sleep environment.

• Melatonin: Can be useful for circadian rhythm issues but is not a sedative.

• Valerian root or magnesium: May help with relaxation, though evidence is mixed.

Conclusion

So—are sleep pills bad for you? They can be, especially with long-term or improper use. OTC sleep aids might seem harmless, but they can lead to next-day grogginess, tolerance, and liver strain. Prescription medications are more potent and carry serious risks when used long-term.

The safest approach is to treat the root causes of insomnia and view sleep aids as a short-term tool—not a nightly habit. Always speak to a healthcare professional before starting or continuing any sleep medication, especially if you're taking other drugs or have underlying health conditions.