15 Concussion Symptoms You Need to Recognize Immediately

A concussion is a type of traumatic brain injury caused by a blow to the head or a violent jolt that causes the brain to move rapidly inside the skull. This sudden movement can create chemical changes in the brain and sometimes stretch and damage brain cells. While often referred to as a “mild” brain injury, concussions should always be taken seriously as they can have significant short-term and long-term effects on your health and well-being.

Understanding concussion symptoms is crucial for prompt recognition and proper management. Symptoms can appear immediately after the injury or may develop hours or even days later. In this comprehensive guide, we’ll explore 15 common concussion symptoms that everyone should know, helping you identify when medical attention is necessary.

1. Persistent Headache

A headache is one of the most common and recognizable symptoms of a concussion. This isn’t just any ordinary headache—it often feels like constant pressure or throbbing pain that doesn’t respond well to typical pain relief methods.

The headache may:

• Start immediately after the injury or develop within hours
• Feel like pressure, tightness, or pounding sensation
• Worsen with physical activity or mental concentration
• Last for days or even weeks in some cases
• Be accompanied by sensitivity to light or noise

Post-concussion headaches can vary in intensity from mild to severe and may come and go throughout the day. If the headache persists or worsens over time, it’s essential to seek medical evaluation as it could indicate a more serious injury.

2. Dizziness and Balance Problems

Dizziness and feeling unsteady on your feet are hallmark symptoms of a concussion. The brain injury can affect the vestibular system, which controls balance and spatial orientation, making simple activities like walking or standing feel challenging.

People with concussions often experience:

• A spinning sensation (vertigo)
• Feeling lightheaded or faint
• Difficulty maintaining balance while standing or walking
• Increased risk of falling or stumbling
• Unsteadiness that worsens with head movements

These balance issues can significantly impact daily activities and increase the risk of additional injuries from falls. It’s important to avoid activities that require good balance, such as climbing stairs alone or driving, until these symptoms resolve.

3. Confusion and Disorientation

Mental confusion is a critical sign of a concussion that should never be ignored. This symptom indicates that the brain injury is affecting cognitive processing and awareness.

Confusion may manifest as:

• Not knowing where you are or what time it is
• Difficulty understanding what others are saying
• Feeling “foggy” or like you’re in a daze
• Inability to recall events immediately before or after the injury
• Asking the same questions repeatedly
• Delayed responses to questions or instructions

If someone appears confused after a head injury, it’s a strong indicator that a concussion has occurred, and immediate medical attention should be sought. This is especially important if the confusion persists or worsens.

4. Memory Problems

Memory difficulties are extremely common after a concussion and can affect both short-term and long-term memory. This symptom can be particularly distressing for the person experiencing it and is often one of the first signs noticed by others.

Memory issues may include:

• Inability to remember the injury itself or events surrounding it
• Difficulty learning and retaining new information
• Forgetting conversations or instructions given recently
• Trouble recalling names, dates, or familiar information
• Losing track of daily activities or appointments

These memory problems typically improve as the brain heals, but they can persist for weeks or months in some cases. Keeping a written record of important information and using reminders can help manage this symptom during recovery.

5. Nausea and Vomiting

Feeling nauseous or actually vomiting after a head injury is a concerning symptom that requires prompt medical evaluation. This occurs because the brain injury can affect the area of the brain that controls nausea and the digestive system.

Key characteristics include:

• Persistent feelings of queasiness or upset stomach
• Vomiting that occurs soon after the injury or repeatedly
• Nausea that worsens with movement or when trying to eat
• Loss of appetite
• Increased sensitivity to smells that trigger nausea

Vomiting, especially if it occurs more than once or several hours after the injury, can indicate a more serious brain injury and requires immediate medical attention. It’s important to stay hydrated, but if vomiting is severe or persistent, medical intervention may be necessary.

6. Sensitivity to Light (Photophobia)

Many people who suffer a concussion develop an increased sensitivity to light, medically known as photophobia. This symptom can make everyday environments feel uncomfortable and even painful.

Light sensitivity may cause:

• Discomfort or pain when exposed to bright lights
• Need to wear sunglasses indoors or in normal lighting
• Difficulty looking at screens (phones, computers, TVs)
• Squinting or closing eyes frequently
• Headaches that worsen in bright environments
• Preference for dimly lit or dark rooms

This symptom can significantly impact daily activities such as working, reading, or watching television. Creating a dimly lit, comfortable environment can help manage this symptom during recovery.

7. Sensitivity to Noise (Phonophobia)

Similar to light sensitivity, many concussion patients experience heightened sensitivity to sounds. Normal everyday noises can seem overwhelming, loud, or even painful to someone with a concussion.

Sound sensitivity characteristics include:

• Normal volume sounds seeming excessively loud
• Difficulty tolerating background noise or multiple sounds at once
• Discomfort in noisy environments like restaurants or crowds
• Need for quiet surroundings to feel comfortable
• Sounds triggering or worsening headaches
• Difficulty concentrating when any noise is present

Managing noise sensitivity involves creating quiet spaces for rest and recovery, using earplugs when necessary, and avoiding loud environments until symptoms improve.

8. Difficulty Concentrating

Concentration problems are among the most frustrating symptoms of a concussion, affecting work, school, and daily activities. The brain injury impairs the ability to focus attention and process information efficiently.

Concentration difficulties may present as:

• Inability to focus on tasks for normal periods of time
• Easily distracted by minor interruptions
• Difficulty following conversations or instructions
• Taking much longer to complete routine tasks
• Mental fatigue from trying to concentrate
• Difficulty multitasking or switching between tasks

Students and workers often notice this symptom significantly impacts their performance. It’s important to take frequent breaks, reduce distractions, and avoid pushing yourself too hard during recovery, as mental rest is crucial for healing.

9. Fatigue and Excessive Tiredness

Overwhelming fatigue is one of the most debilitating concussion symptoms. The brain requires enormous energy to heal, and this increased demand often leaves concussion patients feeling exhausted even after minimal physical or mental activity.

Concussion-related fatigue includes:

• Feeling extremely tired despite adequate sleep
• Need for frequent naps or rest periods throughout the day
• Physical and mental exhaustion from minimal activity
• Difficulty staying awake during normal waking hours
• Energy levels that don’t improve with rest
• Feeling drained after activities that were previously easy

It’s crucial to listen to your body and rest when needed. Pushing through fatigue can actually slow recovery and worsen other symptoms. Gradually increasing activity levels as symptoms improve is the recommended approach.

10. Sleep Disturbances

Paradoxically, while concussion patients often feel exhausted, many also experience significant sleep problems. The brain injury can disrupt normal sleep patterns, making it difficult to get the restorative sleep needed for healing.

Sleep disturbances may include:

• Difficulty falling asleep (insomnia)
• Waking frequently during the night
• Sleeping much more or much less than usual
• Non-restorative sleep (waking up feeling unrefreshed)
• Irregular sleep schedule
• Vivid dreams or nightmares

Establishing good sleep hygiene practices, such as maintaining a regular sleep schedule, creating a dark and quiet sleeping environment, and avoiding screens before bedtime, can help improve sleep quality during concussion recovery.

11. Mood Changes and Irritability

Emotional changes are common after a concussion and can be distressing both for the person experiencing them and their loved ones. The brain injury can affect the areas responsible for emotional regulation, leading to unpredictable mood swings.

Mood symptoms may include:

• Increased irritability or quick temper
• Feeling more emotional than usual (crying easily)
• Mood swings that seem to come out of nowhere
• Feeling anxious, nervous, or worried
• Sadness or depression
• Less patience with others or situations
• Emotional responses that seem disproportionate to the situation

These emotional changes are a direct result of the brain injury and are not a reflection of your character. Recognizing that these mood changes are symptoms of the concussion can help you and those around you respond with more understanding and patience.

12. Slowed Reaction Time

A concussion can significantly slow down how quickly you respond to stimuli, affecting both physical reactions and mental processing speed. This symptom can have serious safety implications, particularly for activities like driving.

Delayed reactions manifest as:

• Taking longer to respond to questions or instructions
• Slower physical reflexes and movements
• Difficulty making quick decisions
• Delayed response to visual or auditory cues
• Feeling like everything is happening in slow motion
• Increased response time in activities requiring quick thinking

This slowed processing can make normally simple tasks feel challenging and can increase the risk of accidents. It’s important to avoid activities that require quick reactions, such as driving or operating machinery, until this symptom resolves and you’ve been cleared by a healthcare provider.

13. Blurred or Double Vision

Vision problems are common after a concussion because the brain injury can affect the neural pathways that control eye movement and visual processing. These vision disturbances can range from mild to severe and can significantly impact daily activities.

Visual symptoms include:

• Blurry vision that comes and goes or remains constant
• Seeing double (two images of a single object)
• Difficulty focusing on objects, especially when reading
• Eyes feeling strained or tired
• Trouble tracking moving objects
• Vision that worsens with eye movement or looking at screens

Vision problems can make reading, using computers, watching television, and even walking safely very difficult. If you experience significant or persistent vision changes after a head injury, a comprehensive evaluation by an eye care specialist or neurologist may be necessary.

14. Ringing in the Ears (Tinnitus)

Many people with concussions experience tinnitus, which is the perception of ringing, buzzing, hissing, or other sounds in the ears when no external sound is present. This can be a constant or intermittent symptom that ranges from mildly annoying to severely disruptive.

Tinnitus characteristics include:

• Ringing, buzzing, hissing, whistling, or roaring sounds
• Sounds that may be present in one or both ears
• Noise that may be constant or come and go
• Sounds that worsen in quiet environments
• Difficulty hearing external sounds over the internal noise
• Disruption to concentration and sleep

While tinnitus often improves as the concussion heals, it can sometimes persist for extended periods. Background noise or white noise can sometimes help mask the tinnitus and make it less noticeable, particularly when trying to sleep.

15. Changes in Taste or Smell

Less commonly discussed but still significant, some people with concussions experience alterations in their sense of taste or smell. The brain injury can affect the olfactory and gustatory systems, leading to these sensory changes.

These changes may include:

• Reduced ability to smell or taste foods
• Complete loss of smell (anosmia) or taste
• Distorted smells or tastes (things smell or taste different than normal)
• Unpleasant taste in the mouth
• Decreased appetite due to altered taste or smell
• Inability to detect strong odors

These sensory changes can affect appetite and enjoyment of food, potentially impacting nutrition during recovery. While these symptoms often improve over time, they can occasionally persist and may require evaluation by a specialist if they don’t resolve.

Main Causes of Concussions

Understanding what causes concussions is essential for both prevention and recognition. A concussion occurs when the brain moves rapidly within the skull, causing it to bounce or twist. This movement can result from various types of impacts or sudden movements.

Sports Injuries

Contact sports are one of the most common causes of concussions, particularly in activities such as football, soccer, hockey, basketball, rugby, and boxing. Collisions with other players, falls, or being struck by equipment can all result in concussive injuries. Even non-contact sports like gymnastics or cheerleading carry concussion risks due to potential falls.

Motor Vehicle Accidents

Car, motorcycle, bicycle, and pedestrian accidents are frequent causes of concussions. The sudden deceleration or impact during a collision can cause the brain to move forcefully within the skull, even if there’s no direct blow to the head. Whiplash-type movements can also result in concussions.

Falls

Falls are the leading cause of concussions, particularly among young children and older adults. Falling from heights, slipping on wet surfaces, tripping over objects, or losing balance can all result in head impacts that cause concussions. Workplace falls and falls at home are both significant contributors.

Physical Assaults

Unfortunately, physical violence including domestic violence, assaults, and abuse can cause concussions. Direct blows to the head, being shaken violently (particularly in infants, leading to “shaken baby syndrome”), or having the head struck against objects can all result in concussive injuries.

Recreational Activities

Activities outside of organized sports can also cause concussions, including playground accidents, amusement park rides, horseback riding, skateboarding, skiing, snowboarding, and other recreational pursuits where falls or impacts to the head can occur.

Combat and Military Service

Military personnel face unique concussion risks from blast injuries, combat-related impacts, and training accidents. Blast waves from explosions can cause concussions even without direct head impact.

Prevention Strategies

While not all concussions can be prevented, there are many effective strategies to reduce your risk of head injuries and concussions in various settings.

Wear Appropriate Safety Equipment

Always wear properly fitted helmets when engaging in activities with head injury risks, including cycling, motorcycling, skateboarding, skiing, snowboarding, and contact sports. Ensure helmets meet safety standards and replace them after any significant impact. In sports, wear all recommended protective gear including mouthguards and padding.

Vehicle Safety Measures

Always wear seatbelts in vehicles and ensure children are in age-appropriate car seats properly installed. Follow safe driving practices, avoid distracted driving, never drive under the influence of alcohol or drugs, and maintain your vehicle in good working condition.

Home Safety

Make your home safer by removing tripping hazards such as loose rugs and clutter, installing handrails on stairs, using non-slip mats in bathrooms, ensuring adequate lighting throughout the home, and using safety gates for young children near stairs. Keep floors dry and clean up spills immediately.

Sports Safety Practices

Follow proper techniques and rules of the game, participate in conditioning programs to improve strength and balance, learn and practice safe playing techniques, ensure proper supervision, especially for youth sports, and never return to play on the same day as a head injury.

Strengthen Balance and Coordination

Engage in exercises that improve balance, coordination, and strength, particularly for older adults who are at higher fall risk. Activities like tai chi, yoga, and balance training can help prevent falls.

Create Safe Environments

In workplaces, ensure proper safety equipment is available and used, follow safety protocols, keep work areas organized and free of hazards, and provide adequate training for activities with head injury risks.

Be Aware of Your Surroundings

Stay alert to potential hazards in your environment, avoid multitasking while walking or moving, be especially careful on uneven surfaces or in unfamiliar areas, and supervise children during play activities.

Frequently Asked Questions

How long after hitting your head can concussion symptoms start?

Concussion symptoms can appear immediately after the injury, but they may also develop hours or even days later. Some people experience symptoms right away, while others may not notice problems until 24-48 hours after the incident. This delayed onset is why it’s important to monitor anyone who has experienced a head injury for several days afterward. If new symptoms develop or existing symptoms worsen, seek medical attention immediately.

What does a concussion feel like?

A concussion often feels like a combination of physical, cognitive, and emotional symptoms. Physically, many people describe it as having a persistent headache, feeling dizzy or off-balance, and being unusually tired. Mentally, it can feel like being in a fog, having difficulty thinking clearly, or feeling confused. Some people describe it as feeling “not quite right” or “off.” The severity and combination of symptoms vary greatly from person to person.

How do you know if you have a concussion?

You may have a concussion if you’ve experienced a blow to the head or violent shaking and subsequently develop symptoms such as headache, dizziness, confusion, memory problems, nausea, sensitivity to light or noise, or changes in mood or sleep patterns. Any loss of consciousness, even briefly, following a head injury strongly suggests a concussion. If you suspect a concussion, it’s important to stop all activities and seek medical evaluation, even if symptoms seem mild.

Can you have a concussion without losing consciousness?

Yes, absolutely. Most concussions do not involve a loss of consciousness. You can have a significant concussion while remaining conscious throughout the incident. The presence or absence of unconsciousness does not determine the severity of a concussion. Many people with serious concussions never lose consciousness, which is why it’s important to watch for other symptoms rather than relying solely on whether someone “passed out.”

When should you go to the emergency room for a concussion?

Seek emergency medical care immediately if you experience severe or worsening headaches, repeated vomiting, seizures or convulsions, loss of consciousness, inability to wake up, increasing confusion or disorientation, slurred speech, weakness or numbness in arms or legs, unequal pupil sizes, clear fluids draining from the nose or ears, or any symptom that significantly worsens over time. For children, seek emergency care if they won’t stop crying, refuse to eat, or show any concerning symptoms.

How long does it take to recover from a concussion?

Recovery time varies widely depending on the individual, the severity of the concussion, and whether it’s a first-time or repeat injury. Most people recover within 7-10 days, though some may take several weeks or even months. Children and teenagers often take longer to recover than adults. A small percentage of people experience post-concussion syndrome with symptoms lasting months or longer. Recovery requires both physical and mental rest, and returning to activities too soon can prolong symptoms or cause further injury.

Is it safe to sleep after a concussion?

Yes, it is safe to sleep after a concussion. The old advice about keeping someone awake after a head injury is outdated. Sleep is actually important for brain healing. However, for the first 24 hours after a significant head injury, it may be advisable to have someone check on you periodically to ensure you can be awakened normally and aren’t showing signs of deterioration. If you’re concerned, consult with a healthcare provider about appropriate monitoring.

Can a concussion cause long-term problems?

While most people fully recover from a single concussion, some individuals may experience lingering symptoms for weeks, months, or longer—a condition called post-concussion syndrome. Multiple concussions, especially when occurring before full recovery from a previous one, can increase the risk of long-term complications including chronic headaches, cognitive difficulties, mood disorders, and in severe cases, chronic traumatic encephalopathy (CTE). This is why proper diagnosis, treatment, and complete recovery before returning to activities are crucial.

References:

• Centers for Disease Control and Prevention – Concussion and Traumatic Brain Injury
• Mayo Clinic – Concussion Symptoms and Causes
• National Institute of Neurological Disorders and Stroke – Traumatic Brain Injury
• BrainLine – What is a Concussion?
• Johns Hopkins Medicine – Concussion