What’s the difference between insomnia and sleep apnea?

A lot of things might keep you up all night. And plenty of things might wake you up over and over again. But if the occasional rough night starts happening more often – and can’t be explained by outside factors, like a car horn, crying baby or barking dog – it might be a sign of something more serious like a sleep disorder.

Two of the most common sleep disorders are insomnia and sleep apnea. Both disorders can cause chronic sleep deprivation, especially if left untreated.

Sleep deprivation can increase your risk of serious health problems, including cardiovascular disease, high blood pressure, type 2 diabetes, obesity and depression. It can make existing health conditions worse or more difficult to manage, too.

At the same time, the lack of sleep can leave you feeling tired all the time, raising your risk of accidents and injuries. Sleep disorders can also make it harder to think clearly, concentrate and make decisions, and cause you to feel moody or irritable. Over time, these effects can interfere with your day-to-day life, including by straining your relationships and hurting your performance at work or school.

Let’s take a quick look at insomnia and sleep apnea to help you understand how they affect sleep, as well as how they’re alike and different. If anything sounds familiar or you’re concerned another medical condition may be affecting your sleep, it’s best to talk to a medical professional for a thorough exam and diagnosis.

What is insomnia?

People who have insomnia often have a lot of trouble falling asleep and staying asleep. They also tend to feel like they can’t turn their brain off or stop their thoughts from racing. As a result, they don’t sleep well, tend to feel tired during the day and may not function as well as they usually would. They may also begin to feel anxious or dread going to bed, becoming hyper-aware of how challenging it is to fall asleep.

Most people experience insomnia once in a while, such as before or after an exciting, stressful or difficult time. But about 12 percent of people in the United States experience chronic insomnia,¹ which leads to ongoing sleep deprivation.

Insomnia symptoms

While each individual’s experience may be different, common symptoms of insomnia include:

• Trouble falling asleep

• Waking up during the night or too early

• Feeling tired during the day

• Feeling down, irritable or anxious

• Trouble focusing or remembering things

• Making more mistakes or having more accidents

• Worrying about sleep

Causes of insomnia

Stress or pain is often the root cause of short-term insomnia. For example, people who are experiencing difficulties in their relationships or at work, or going through a major life event – such as a divorce or job loss – may develop insomnia. Likewise, those who feel discomfort from, say, a muscle strain or are recovering from an injury may also develop it. In these cases, the symptoms of insomnia often lessen as a person recovers from the stress or pain.

Other short-term causes can include having an erratic sleep schedule, such as due to travel and switching time zones, or not following a set schedule. Doing so can throw off your internal clock – circadian rhythm – and natural sleeping patterns, making it harder for your mind and body to know when it’s time to sleep.

However, if insomnia symptoms are ongoing and/or aren’t easily linked to a current situation, it could be a sign of an underlying physical or mental health condition. These might include anxiety disorders, post-traumatic stress disorder, cancer, diabetes or heart disease, or others. Certain prescription medications can cause insomnia as a side effect, too.

As mentioned above, it’s best to consult a health care professional for an evaluation and diagnosis.

Treating insomnia

Treatment for chronic insomnia often includes cognitive behavioral therapy (CBT), commonly referred to as “talk therapy,” which can help address the unhelpful thinking patterns related to sleep. In addition, identifying and managing any underlying medical or mental health conditions is important.

Practicing good sleep hygiene – such as following a sleep routine and creating a comfortable environment – is also often recommended.

What is sleep apnea?

There are three kinds of sleep apnea – obstructive, central and mixed. In each case, the disorder causes you to stop breathing for short periods throughout the night. Each time you do, your brain alerts you to wake up to take a breath, though you may not remember waking up. In severe cases, this sleep apnea event cycle may repeat hundreds of times per hour.

Sleep apnea events cause your blood oxygen levels to drop, which makes it harder for your brain and body to function well. The reason this happens and how often depends on the type of sleep apnea you have and the severity of your condition.

Types of sleep apnea

With obstructive sleep apnea (OSA), this happens because your tongue and other muscles in your throat relax during sleep in a way that blocks your airway. This makes it hard to breathe, so your brain alerts you to wake up and breathe. Depending on the severity of the condition, the cycle could repeat hundreds of times throughout the night.

Obstructive sleep apnea is the most common type of sleep apnea – and the one people are usually referring to if they just say, “sleep apnea.” It’s estimated up to 30% of adults have obstructive sleep apnea – but the vast majority don’t know they do.^2,3,4

Central sleep apnea (CSA) is rare, affecting fewer than 1% of adults in the general population.⁵ It happens when your brain briefly stops signaling you to breathe during sleep. This can lower oxygen and raise carbon dioxide levels in your blood, triggering your brain to restart and you to wake up gasping for air. How often this happens depends on the severity of your condition.

The third type of sleep apnea is a mix of obstructive and central, called complex or mixed sleep apnea (CompSA). It’s diagnosed when you experience symptoms of both types of sleep apnea.

Sleep apnea symptoms

The signs and symptoms for obstructive and central sleep apnea often overlap:

• Waking up gasping for air

• Waking up with a dry mouth, sore throat or headache

• Restless while sleeping, tossing and turning

• Feeling tired during the day, unintentionally falling asleep during regular activities

• Difficulty concentrating or remembering things

• Decreased sex drive

• Mood swings or irritability

Meanwhile, consistent, loud snoring and being overweight or gaining weight are more often linked to obstructive sleep apnea.

Treating sleep apnea

A wide range of treatments are available to manage sleep apnea – from adjusting behaviors and routines to over-the-counter dental appliances, prescription medical devices, implantable therapies and medications.

Pursuing better sleep

Insomnia and sleep apnea can co-occur and their symptoms often overlap. If you’re struggling to consistently get enough quality sleep, consult with a healthcare provider, sleep specialist or mental health professional. They can help identify the cause, make a diagnosis and develop a treatment plan tailored to your unique situation, medical history and lifestyle needs.

Most sleep disorders can be effectively treated or managed – and many people are able to sleep soundly and feel like themselves again.

Sources

¹ American Academy of Sleep Medicine, 12% of Americans are diagnosed with chronic insomnia.

² American Medical Association, What doctors wish patients knew about sleep apnea. April 1, 2022

³ Cleveland Clinic, Sleep Apnea: What It Is, Causes, Symptoms & Treatment. January 15, 2025.

⁴ Johns Hopkins Medicine, Obstructive Sleep Apnea. Accessed August 5, 2025.

⁵ SleepApnea.org, Central Sleep Apnea. November 18, 2022.

Cleveland Clinic, Central Sleep Apnea: What It Is, Causes, Symptoms & Treatment. January 27, 2024.

HealthHub, The Importance of Sleep. November 15, 2022.

Mayo Clinic, Insomnia - Symptoms and causes. January 16, 2024.

Sleep Foundation, Sleep Apnea vs. Insomnia. July 10, 2025.