Depression Types What Is Central Nervous System (CNS) Depression? By Toketemu Ohwovoriole Toketemu Ohwovoriole Toketemu has been multimedia storyteller for the last four years. Her expertise focuses primarily on mental wellness and women’s health topics. Learn about our editorial process Updated on December 26, 2023 Medically reviewed Verywell Mind articles are reviewed by board-certified physicians and mental healthcare professionals. Medical Reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Daniel B. Block, MD Medically reviewed by Daniel B. Block, MD Daniel B. Block, MD, is an award-winning, board-certified psychiatrist who operates a private practice in Pennsylvania. Learn about our Medical Review Board Fact checked Verywell Mind content is rigorously reviewed by a team of qualified and experienced fact checkers. Fact checkers review articles for factual accuracy, relevance, and timeliness. We rely on the most current and reputable sources, which are cited in the text and listed at the bottom of each article. Content is fact checked after it has been edited and before publication. Learn more. by Karen Cilli Fact checked by Karen Cilli Karen Cilli is a fact-checker for Verywell Mind. She has an extensive background in research, with 33 years of experience as a reference librarian and educator. Learn about our editorial process Print Maskot / Getty Images Table of Contents View All Table of Contents How CNS Depression Works? Symptoms How CNS Depression Is Diagnosed What Causes CNS Depression? Treatment for CNS Depression When to Seek Help for CNS Depression Close CNS depression is a form of depression caused by the misuse of CNS depressants. CNS depressants are substances that can slow down your central nervous system. Some common examples include opioids, sedatives, and hypnotics. These drugs are used to treat pain, anxiety, sleep disorders, and stress. Your central nervous system is made up of your brain and spinal cord and controls functions like your blood circulation and digestion. At a Glance The overuse of depressants can lead to symptoms of CNS depression, including slowed reflexes, lightheadedness, fatigue, and difficulty breathing. Depressants affect GABA, an inhibitory neurotransmitter that slows down activity in the brain. When severe, CNS depression caused by substances such as opioids, alcohol, barbiturates, benzodiazepines, and sleeping medications can be fatal. How CNS Depression Works? CNS depressants work by increasing the activity of a neurotransmitter in your brain, called gamma-aminobutyric acid (GABA). An increase in the activity of GABA in your brain leads to a slowdown of your brain activity. CNS depression is prevalent among people who use these substances recreationally. CNS depression varies in severity. Sometimes these effects can be mild, but they can also be severe and potentially dangerous. You might experience mild CNS depression from the prescribed use of CNS depressants or severe CNS depression from the misuse of CNS depressants, traumatic brain injury, or certain other conditions. Symptoms of Central Nervous System Depression People living with CNS depression experience varying symptoms; two people living with the condition might not have the same ones. Some of the most common but mild symptoms that help identify the condition include: Slurred speechSlowed reflexesHigher pain tolerance Drowsiness Headaches Lightheadedness In situations where the condition has progressed in severity, a person will experience more severe symptoms, some of which include: ConfusionExtreme fatigueDifficulty breathing Difficulty staying awake Fingers and lips that start to turn blue Low blood pressure Memory problems How Depressants Affect Your Body How CNS Depression Is Diagnosed People using central nervous system depressants might sometimes experience mild depression as a side effect. This would typically go away when you stop using the medication or when your body adjusts to the medication. Before a diagnosis of CNS depression can be made, your doctor will need to examine your medical history and conduct a series of tests. If you have recently been prescribed CNS depressants or misused any CNS depressants, this will be the most likely culprit. Another major cause of CNS depression in people who have no history of using CNS depressants is brain injury. If your doctor suspects that a brain injury or tumor is the cause of your depression, they might order a CT scan, an MRI scan, or both. Long-Term Effects of Antidepressants What Causes CNS Depression? The misuse of certain substances causes CNS depression. These substances are referred to as CNS depressants because they affect the activity of your CNS. People either misuse CNS depressants by taking more than prescribed or taking them when they are not prescribed to alter their minds. The most common substances that cause CNS depression include: Opioids Opioids are strong pain relievers that are obtained from opiates like heroin and oxycodone. They have a high risk of becoming addictive, which is why they are often prescribed in small doses for only short periods. Opioids are often misused and used recreationally, making them one of the leading causes of CNS depression. Some common types of opioids typically prescribed for severe pain include Vicodin and Percocet. Alcohol Although many people don’t think of alcohol as a drug, it’s one of the most common and often abused drugs in the world today. Alcohol abuse can lead to addiction and CNS depression. Barbiturates Barbiturates are drugs typically used to treat anxiety and sleep disorders. Some of the most common types include Luminal, Amytal, and Nembutal. Barbiturates are powerful medications, and over time medical professionals have shifted from using them to treat anxiety and sleep disorders to being used as anticonvulsants (anti-seizure medications). Benzodiazepines Benzodiazepines, also known as Benzos, are also used to treat anxiety and sleep disorders, although they are considered less addictive than barbiturates. Xanax, Valium, and Prosom are some of the most common types of Benzodiazepines. Sleeping Medication CNS depressants slow down brain activity, making them a great treatment for sleeping disorders. Sonata and Ambien are two types of sleeping medication that are CNS depressants. Although they have a lower risk of dependency than other CNS depressants, long-term use may cause the condition. If you or a loved one are struggling with substance use or addiction, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 for information on support and treatment facilities in your area. For more mental health resources, see our National Helpline Database. Traumatic Brain Injury In certain cases, CNS depression could also be caused by a stroke, brain trauma, an aneurysm, or a tumor. Some research shows that even conditions that don’t directly affect the brain, like diabetes or kidney and heart disease, could cause CNS depression. Other Factors That Affect CNS Depression Combining one or more CNS depressants often causes CNS depression. Alcohol is typically a culprit in these sorts of situations. This is why these medications specifically prohibit you from drinking alcohol while taking them. People who already have a history of drug or alcohol dependency are at greater risk of developing severe CNS depression, which is why doctors take a thorough look into your medical history before prescribing CNS depressants for any condition. Treatment for CNS Depression Treatment for CNS depression depends on its cause. If it is a result of the misuse of CNS depressants, certain medications are prescribed. Naloxone Naloxone is administered to people who are suffering from an opioid overdose. It can either be administered as an injection or given intravenously. Flumazenil Flumazenil is administered to people who are experiencing severe side effects from using Benzodiazepines. Flumazenil is also used to treat an overdose of medications. However, it’s a short-acting drug and might need to be administered several times before a person recovers. If severe CNS depression is left untreated, it can be fatal for the person living with the condition. How Long Does Withdrawal From Benzodiazepines Last? When to Seek Help for CNS Depression Mild CNS depression is typically nothing to worry about. CNS depressants work by slowing down your brain activity, which is why it’s great for conditions like anxiety and sleep disorders. However, if you find that your CNS depressants affect your daily functioning, speak to your doctor about it. They’ll decide if you need to be taken off the medication, switched to another form of the medication, or if your dosage needs to be adjusted. However, severe CNS depression needs immediate treatment, or it could result in heart failure or even death. If you are on CNS depressants and suspect it’s making you more lethargic than you should be, don’t stop it until you speak to your doctor. Suddenly stopping the medication could result in more harm than good. What This Means For You Mild CNS depression is often the goal of taking some CNS depressants, especially sleep and anxiety disorders. It’s important to take the medication exactly as your doctor prescribes to avoid a more severe form of the condition. It would be best to inform your doctor as soon as you experience any side effects that you find intolerable. 5 Sources Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. National Institute on Drug Abuse. Prescription CNS depressants drugfacts. National Institute on Drug Abuse. What classes of prescription drugs are commonly misused? Skolnik AB, Wilcox SR. Toxic alcohol poisoning. In: Critical Care Secrets. Elsevier; 2013:558-561. doi:10.1016/B978-0-323-08500-7.00095-3 Cordovilla-Guardia S, Lardelli-Claret P, Vilar-López R, López-Espuela F, Guerrero-López F, Fernández-Mondéjar E. The effect of central nervous system depressant, stimulant and hallucinogenic drugs on injury severity in patients admitted for trauma. Gaceta Sanitaria. 2019;33(1):4-9. doi:10.1016/j.gaceta.2017.06.006 National Institute on Drug Abuse. Naloxone drugfacts. By Toketemu Ohwovoriole Toketemu has been multimedia storyteller for the last four years. Her expertise focuses primarily on mental wellness and women’s health topics. See Our Editorial Process Meet Our Review Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Helpful Report an Error Other Submit