Post-Concussion Syndrome

Post-concussion syndrome is when recovery from a concussion takes an unusually long time. While most people will eventually recover completely, there are rare cases where the effects are permanent. However, the symptoms are often treatable and most people can minimize the impact of this condition on their lives.


What is post-concussion syndrome?

Post-concussion syndrome (PCS) is when you have concussion symptoms that last months or even a year or more after your initial injury. The symptoms can affect you in many ways, including how your body and brain function, as well as how you experience emotions.

Usually, concussion symptoms go away within two to six weeks after you experience an injury. People receive a PCS diagnosis when their concussion symptoms continue (persist) for much longer. Some symptoms are extremely subtle. Because of that, it’s a good idea to pay attention to your body and trust your instincts if something doesn’t feel right after you’ve had a concussion.

You should get immediate help if you have thoughts about harming yourself or others, or if you suspect someone is in danger of harming themselves.

Persistent post-concussion syndrome

There’s only one subtype of post-concussion syndrome. Persistent post-concussion syndrome is when symptoms continue for an extremely long time. The time limit on this varies and often falls to a healthcare provider’s judgment. Providers commonly use this diagnosis when symptoms last longer than three months, six months or even a year after an injury.

How common is post-concussion syndrome?

Concussions are fairly common, but it’s hard for experts to estimate the exact number of people that experience one each year. Many people who suffer a concussion don’t seek medical care. Experts estimate that there are between 1.6 million and 4 million new cases of concussions in the U.S. each year.

Studies estimate that about 15% of people with a concussion will also experience PCS. However, researchers also have strong reason to believe that’s an underestimation. Some of the reasons for that include:

  • People going without medical care. As noted above, not everyone with a concussion gets medical attention. That may also be true for many whose symptoms last long enough to be PCS.
  • No widely agreed upon criteria. Different organizations have different criteria for PCS, and some have changed their criteria over time.

PCS is tricky to diagnose. Some concussion symptoms are difficult to detect. Emotional and behavioral changes are examples of this. In the hospital, they may not stand out, or a healthcare provider might not have a way to know how a person usually behaves. That can make it hard to spot behavioral changes due to a concussion.


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Symptoms and Causes

What are the symptoms of post-concussion syndrome?

Post-concussion symptoms themselves are usually the same as concussion symptoms — they just last for much longer.

It’s important to note that any loss of consciousness (being “knocked out”) — no matter how brief — after an impact to the head or after a body impact that causes whipping of the head (whiplash) means you probably have a concussion. If you’re with someone who becomes unconscious after a head impact or whiplash event, they need medical attention — even if they regain consciousness quickly.

Another important fact to remember is, you don’t need to lose consciousness to experience a concussion. Many people who experience the kinds of impacts or events described above say things might not seem worrying at first glance. Common statements after a concussion event that doesn’t cause a person to lose consciousness include:

  • “I have a headache.”
  • “I got my bell rung.”
  • “I feel out of it.”
  • “I’m seeing stars.”

The symptoms of a concussion tend to fall into four categories:

  • Physical.
  • Sensory.
  • Mental (focus/concentration changes).
  • Emotional or behavioral changes.

Physical symptoms

Physical concussion symptoms can include:

Sensory symptoms

Sensory symptoms can affect your five main senses (vision, hearing, smell, taste and touch). They can also affect related senses, such as balance. They include:

Mental symptoms

Symptoms that affect your mental state can include:

  • Memory loss (amnesia).
  • Trouble concentrating.
  • Mental fogginess.
  • Slowed thought processes (taking longer to think of things that previously gave you little or no difficulty).

Behavioral symptoms

A concussion can also affect your behavior. Possible behavioral symptoms are:

  • Irritability.
  • Feeling unusually depressed or sad.
  • Anxiety.
  • Agitation.
  • Mood swings.
  • Feeling restless
  • Thoughts of self-harm or suicide.

Seek help immediately if you’re having thoughts about harming yourself or others, or if someone is in danger of self-harm. Resources that can help you include:

  • National Suicide and Crisis Lifeline (United States): This line can help you if you have suicidal thoughts or impulses. You can also call this line even when you’re not in crisis. To call this line, dial 988. You can also get help via text message. To do so, text HELLO to 741741.
  • 911 (or your local emergency services number): You should call 911 (or the local emergency services number) if you feel like you’re (or someone you know is) in immediate danger of self-harm or suicide. Operators and dispatchers for 911 lines can often help people in immediate danger because of a severe mental crisis and send first responders to assist.

What causes post-concussion syndrome?

Experts don’t know exactly why post-concussion syndrome affects only some people who experience a concussion. They suspect it’s a combination of factors adding up.

What are the risk factors for post-concussion syndrome?

Several risk factors can make PCS more likely to happen. Some of these include:

  • Past concussion(s) or head injuries. Your risk of PCS goes up with every successive concussion or head injury.
  • Concussions with complications. You’re more likely to experience PCS if the concussion causes other complications that affect your brain or skull. Some examples include midline shift (the brain moving off-center inside your skull), a skull fracture (a broken bone) or bleeding inside the skull or brain.
  • Having other brain-related conditions. People with conditions like attention-deficit/hyperactivity disorder (ADHD) or learning difficulties may have a higher risk of developing PCS.
  • Having a history of behavioral conditions. People with conditions such as anxiety, depression, bipolar disorder, etc. may also be at higher risk of developing PCS.
  • Greater number of concussion symptoms. Having more concussion symptoms soon after an injury can be a sign of a higher PCS risk.
  • More severe concussion symptoms. Experiencing more severe symptoms can make you more likely to develop PCS.


What are the complications of post-concussion syndrome?

There are many possible complications of post-concussion syndrome. They’re all tied to experiencing lingering concussion symptoms. It’s uncommon, but some people experience post-concussion symptoms that last for years or are even permanent.

Possible complications include:

  • Pain medication overuse.
  • Problems thinking or focusing.
  • Memory loss.
  • Trouble working or being unable to work at all.
  • Executive dysfunction.
  • Long-term sleep disruptions.
  • Problems participating in your daily routine, including activities like household chores, bathing, grooming and getting dressed.
  • Behavioral changes, especially aggression, anxiety or depression.
  • Self-harm and suicidal thoughts.

Diagnosis and Tests

How is post-concussion syndrome diagnosed?

There’s no way to diagnose PCS directly because no specific test can confirm a concussion. Instead, a healthcare provider diagnoses a concussion — and later, PCS — based on their clinical judgment and a person’s symptoms. They’ll do that using several tools and methods, including:

  • A physical and neurological (nervous system function) exam.
  • Talking to you about the injury that caused your concussion and your symptoms since then.
  • Imaging scans like computed tomography (CT) scans, magnetic resonance imaging (MRI) scans or X-rays (these can help diagnose or rule out complications like skull and neck fractures, brain bleeds and other brain injuries).

If a healthcare provider suspects you have PCS, they’ll ask you to schedule follow-up visits to track any changes in your symptoms. They may repeat many of the same tests or ask you the same questions at each follow-up visit. They do that to track your symptoms and look for any changes, even subtle ones, which signal shifts in your condition.

Other tests your provider may recommend can vary depending on your medical history and symptoms. Your healthcare provider can tell you more about their recommended tests and why they think these might help.


Management and Treatment

How is post-concussion syndrome treated, and is there a cure?

Concussions and PCS aren’t considered “curable,” but there are treatment plans to allow for recovery. This means there’s usually no direct treatment or cure for PCS either.

For most people, your brain simply needs time to recover. That means paying attention to your symptoms to pace yourself and taking breaks when symptoms get worse. There are also some treatments that may help your symptoms and improve your recovery.

Symptom-specific treatments fall under these categories:


Healthcare providers no longer commonly suggest pain medications to help you get through your daily activities as you recover from concussion. That’s because if your symptoms worsen with an activity, the medication will keep you from being able to tell right away. That can cause a “rebound” of your symptoms once the medication wears off.

Instead, you should try and pace yourself as the symptoms get worse. This means slowing down and resting to allow symptoms to improve before continuing an activity.

You can take medication later in the day after you’ve been active to allow for better rest and recovery. Over-the-counter (OTC) medications for pain include acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs), to treat headaches at the end of the day. Your provider might prescribe additional medications if over-the-counter medications aren’t enough to manage your symptoms.

Occasionally, a provider may also consider a nerve block for the occipital nerve (at the back of your head) as a possible treatment.


Drugs like promethazine (Phenergan®), ondansetron (Zofran®) or metoclopramide (Reglan®) can relieve nausea or motion-sickness-like symptoms. However, these do require a prescription.

Sleep problems

Part of recovery when you have a concussion or PCS is to have a set schedule for going to bed each night. If sleep is difficult, supplements that affect your body’s natural sleep cycle, such as melatonin, may help when you take them at least an hour before bed. Some prescription and over-the-counter medications may also help. Consult with your provider before taking medications or supplements to help you sleep.

Sensory problems

People with concussions or PCS often experience light and noise sensitivity. That can cause them to feel overwhelmed in bright, loud or crowded environments.

To help manage this, try to limit the environment’s effects on you. Some helpful accessories include a brimmed hat, sunglasses and ear protection (such as silicone ear plugs). You should also consider picking out a nearby spot that’s quiet and calm prior to an activity. That way, you can go rest there if the environment becomes overwhelming and you need a break.

Certain types of rehabilitation or therapy can also help restore your sensory abilities. Vestibular physical therapy, vision therapy and other approaches may also work to bring these systems back to balance and make your symptoms better.

Concentration and focus problems

Speech-language therapy may help to retrain several abilities that might be affected after a concussion. These include your ability to read, focus and process and retain information.

Behavior concerns

Stress, anxiety and depression are common in everyday life. With concussion or PCS, these stresses can feel like someone is using a magnifying glass on them. Things you previously had no trouble managing can feel more stressful and challenging.

Talking to a behavioral specialist, such as a psychologist or psychiatrist trained in concussion, can help. They can help you learn to manage these feelings. Your provider can also prescribe medications to help improve how you experience feelings of anxiety, stress, anger or depression.


People with concussions or PCS are commonly told to rest. But new research shows that after just a couple days of rest after injury, low-level exercise activities can help start the recovery process. These shouldn’t include weight training or sports activities, as these are too intense.

Some examples of low-level activities that may help are riding a stationary bike or taking a slow, gentle walk. You can do these for 20 to 30 minutes every day. These activities shouldn’t make your symptoms worse. If they do, decrease how much effort you’re putting into them. That includes slowing down and taking breaks.

The focus of these activities is how long you spend on them. Speed or distance should not be priorities. Your objective is to get moving again — and to do so slowly and easily — so you don’t make yourself feel worse. You should also talk with your provider for guidance on how to increase your physical activity levels safely.

What are the possible side effects or complications of treatment?

The possible complications and side effects of treatment depend strongly on the treatments themselves, among other factors. Your healthcare provider is the best person to tell you more about what’s possible for you, what to watch out for and what you can do to minimize or manage complications or side effects from any treatments they suggest.


Can I lower my risk of developing post-concussion syndrome or prevent it?

Post-concussion syndrome happens unpredictably. Because of that, there’s no specific way to prevent it. The best way to prevent it is to make it as easy as possible for your brain to heal after a concussion.

Follow your healthcare provider’s instructions to help your post-concussion recovery. Some of the most common guidelines include:

  • Rest your body and brain. Too much physical activity can aggravate concussion symptoms. Likewise, putting too much effort and strain on your brain can also do more harm than good. When symptoms of concussion get worse, slow down or take a break. Physical and mental rest are very important for concussion recovery, especially in the first few days after a concussion. Talk with your medical team about how to gradually return to your daily activities after those first few days.
  • Increase activity gradually. Your provider will give you instructions on how to exercise your body and brain after your initial rest period. If symptoms reappear or worsen, go back to your previous activity level and contact your provider.
  • Avoid anything that might cause another concussion. PCS is much more likely with repeated head impacts and concussions. A second concussion soon after the first one is also extremely dangerous — and can even be deadly. Athletes should never be allowed to keep playing if there’s even a possibility that they have a concussion.

Outlook / Prognosis

What’s the outlook for post-concussion syndrome?

In general, the outlook for PCS is good. Most people with PCS eventually recover and their symptoms stop. How long this takes can vary. Some people fully recover within weeks or months. For others, it may take a year or longer.

Unfortunately, some people may have permanent effects from PCS. In these cases, managing the symptoms might be possible. Your healthcare provider will tell you more about possible treatments and how you can minimize or manage your symptoms.

Living With

How do I take care of myself?

If you have post-concussion syndrome, managing your symptoms will vary depending on which symptoms you’re experiencing. Your healthcare provider can suggest treatments to help your body and brain heal most effectively. They can also monitor your symptoms and determine what changes in your care you may need, if any.

When should I see my healthcare provider, or when should I seek care?

Seek help immediately if you were unconscious for any length of time after a blow to the head.

You should talk to a healthcare provider anytime you still have symptoms 24 hours after an injury to your head and/or neck. You should also get medical attention if you continue having concussion-related symptoms more than two weeks after the injury.

After a healthcare provider diagnoses you with a concussion, see your provider as often as they recommend. Regular visits are important for them to track changes in your symptoms and treat them accordingly. You should also see your provider if:

  • Your symptoms change in a way that affects your daily routine or regular activities.
  • You notice that your treatments or medications aren’t working as well as they did before.

When should I go to the ER?

Most symptoms or complications of concussions and PCS aren’t medical emergencies. However, there are two major exceptions:

  • Suicidal thoughts or behaviors. If you or a loved one is in immediate danger of self-harm, dial 911 or your local emergency services number. You can also dial the National Suicide and Crisis Lifeline at 988 if you’re in the United States and you’re experiencing suicidal thoughts or impulses — even if you’re not currently in crisis — or text HELLO to 741741.
  • Seizures. If you have a seizure (or any unexplained loss of consciousness), especially if it’s the first time, get medical attention as soon as possible. Call 911 (or your local emergency services number) immediately if you or someone you’re with has a seizure that lasts more than five minutes, or if they have back-to-back seizures without becoming fully awake and alert between them.

Additional Common Questions

What is the best treatment for post-concussion syndrome?

The best treatment for post-concussion syndrome varies. What works for one person may not be as helpful for someone else. That’s partly because there’s no way to directly treat PCS, meaning the treatments depend on your symptoms. Your healthcare provider can tell you what treatments they recommend and why.

What is the most common symptom of post-concussion syndrome?

Headaches are the most common symptom of PCS (and concussions in general).

A note from Cleveland Clinic

For most people, PCS means recovery from a concussion takes longer than usual. But in rare cases, it can last years or even be permanent. PCS can also be frustrating because it’s an illness that isn’t visible to others. The symptoms of it can be disruptive, unpleasant or even disabling.

While concussions and PCS aren’t directly treatable, many treatments can help you manage your symptoms. You can also reduce your risk of developing PCS by following your healthcare provider’s guidance while you’re recovering from a concussion. That way, you can potentially limit how long concussion symptoms last and how they affect your life.

Medically Reviewed

Last reviewed on 04/11/2023.

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