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What are the dangers of using over-the-counter medications to help you sleep?

Getting too little sleep can lead to a lot of issues. And even though it’s a problem that affects so many people, it’s also one of the most commonly overlooked health issues in the United States. An estimated 50 to 70 million Americans suffer from chronic sleep disorders and wakefulness that can hinder their daily functioning and adversely affect their health and longevity.

In fact, a report by the National Sleep Foundation shows that as many as 29% of those who responded to a poll reported that they fell asleep or felt very tired at work withing the past month. More concerning, 36% reported being drowsy or even falling asleep behind the wheel of a vehicle in the past year. And feeling tired isn’t the only issue that can result from lack of sleep – many also experience things like headaches and depression as well.

So, it should come as no surprise that over-the-counter (OTC) sleep aids are a big business in the U.S., where it’s estimated that consumers spent more than $425 million on melatonin supplements in 2018 alone.

Unfortunately, many people assume that because these sleep aids are offered without a prescription, they are totally safe. However, regular, long-term use of OTC sleep medicines can lead to some potentially serious side effects.

What’s in popular OTC sleep formulations?

When you look for an over-the-counter sleep aid, you’re confronted with a number of options. There are more natural options such as melatonin, valerian, and chamomile, as well as pharmaceutical products that typically contain antihistamines as their primary active ingredient – including big brand names such as Unisom, NyQuil, Tylenol PM, and others.

As we said, melatonin a popular option, mainly because it’s considered more natural than many alternatives. Melatonin is a hormone that occurs naturally in the body (though commercial supplements are made synthetically), and while it’s responsible for regulating the body’s circadian rhythm, or sleep-wake cycle, it doesn’t directly make you sleepy.

Valerian root and chamomile are derived from plant sources. They contain chemical compounds that may help reduce anxiety and improve sleep by binding to receptors in the brain called GABA receptors, which essentially calms the central nervous system.

More often though, people turn to sleep aids containing antihistamines (usually diphenhydramine, doxylamine succinate), which work by blocking certain brain chemicals (as the name suggests, histamines), which can have a sedating effect. Unfortunately, they can also have negative side effects when taken in large doses or for long periods of time.

What are the side effects and risks?

The primary risk associated with using over-the-counter products containing antihistamines as sleep aids stems from the fact that many of them contain additional drugs. For example, common cold and cough formulations like NyQuil or Robitussin tend to have three types of active ingredients: a pain reliever (usually acetaminophen), a cough suppressant (usually dextromethorphan), and an antihistamine.

Taking too much acetaminophen can cause serious liver damage, and it’s the second most common cause of liver failure requiring a transplant. This is why it’s also important to abstain from drinking alcohol while taking any medications containing acetaminophen.

Dextromethorphan is another concern, as taking too much can induce toxic psychosis, a mental condition that causes confusion, hallucinations, as well as mental problems like paranoia and violent tendencies.

Additionally, antihistamines like diphenhydramine are anticholinergic, which means they block the activity of a brain chemical called acetylcholine that plays a role in brain functions like attention, alertness, learning and short-term memory.

This is anticholinergic blocking effect presents more serious issues for older adults. It’s been shown to cause or exacerbate problems like confusion, constipation and difficulty with urinary retention, and there is some evidence to suggest that long-term use can even predispose people to dementia.

Risk of overdose

As with all medications, it’s important to pay attention to the correct dosage. While things like melatonin and valerian are naturally occurring chemicals and there is a relatively low risk of serious consequences from taking too much, antihistamines can have serious complications when taken in high doses, possibly leading to coma and death due to respiratory distress, cardiac arrest, or seizure.

More often, the side effects of taking too much over-the-counter sleep medications include symptoms such as:

  • Headache
  • Dizziness
  • Drowsiness
  • Nausea and vomiting
  • Depression and anxiety
  • Stomach cramps
  • Mild tremors
  • Low blood pressure
  • Increased heart rate
  • Blurred vision
  • Confusion
  • Loss of balance

Can over-the-counter (OTC) sleep medications be addictive?

For most types of OTC sleep medications, the risk of addiction is quite low when taken as directed. But when taken too often, taken in extremely high doses, or when abused recreationally, there is a risk of developing a physical dependence.

Physical dependence means that the person will difficulty sleeping without taking the medication, and they may also experience other symptoms that are indicative of dependence and withdrawal.

These symptoms may include:

  • Anxiety
  • Chills
  • Cravings
  • Depression
  • Insomnia
  • Restlessness
  • Stomach pain and nausea
  • Shaking and tremors

Fortunately, the physical symptoms can be easily managed with support from a medical professional. The bigger issue is that people who abuse these medications may also develop a mental dependence, which can be more difficult to treat and often requires undergoing medically supervised detox and therapy at an rehab facility like Enterhealth Ranch or the Enterhealth Outpatient Center of Excellence.

What you should do if you have trouble sleeping?

While these kinds of medications can be helpful for short-term relief from insomnia, they shouldn’t be used all the time. In those 65 and older, they should probably be avoided altogether, as the risks presented far outweigh the benefits.

For those who have chronic sleep issues, the best thing to do is speak to your doctor or a sleep specialist about the problem. Be honest with them and make sure to tell them about medications you have or are currently taking so they can determine if there are any negative interactions taking place.

Many times, when we can’t sleep it’s due to other factors like stress, anxiety, pain or nerve problems, and treating the symptom (i.e., not sleeping) isn’t the best course of action.

In a lot of cases, things like behavioral therapy, as well as lifestyle changes like getting more activity during the day, establishing a routine sleep schedule, and cutting out things like caffeine or alcohol are far more effective than medications. These strategies can be used long term and are sure to positively affect your overall health and well-being too.

Get Help with addiction with Enterhealth

Now, through both our inpatient rehab or outpatient treatment, Enterhealth offers a science-based approach that combines state-of-the-art assessments with anti-addiction medications and proven behavioral therapies to help patients experience success in their recovery. If you or someone you love needs help, call us today at 800.388.4601 or visit