Introduction
A concussion is a head injury that temporarily disrupts how the brain works. Most people recover well, but symptoms can last days to weeks, and after-effects sometimes linger. Treating every significant head impact as a possible concussion keeps responses safer.
Symptoms may appear immediately or hours to days later. They range from headache, nausea, dizziness, and confusion to memory gaps, sleep change, irritability, and light or noise sensitivity. Loss of consciousness is less common but important when it happens.
First response focuses on safety, monitoring, and getting medical evaluation—not on “toughing it out” or returning to sport or driving. A person may seem fine at first; delayed symptoms are still possible, so observation matters.
This page explains recognition and sensible first aid while emphasising professional care. It is not a substitute for emergency assessment when red-flag signs appear, and it does not recommend unsafe do-it-yourself brain treatments.
Overview
The brain has a soft, jelly-like consistency and is cushioned by cerebrospinal fluid. A blow, fall, or violent jolt to the head or neck can still shake the brain enough to impair function.
Concussions are often described in grades by symptom duration and whether consciousness was lost, but any suspected concussion deserves medical attention.
Bleeding in or around the brain can be life-threatening. Monitoring after injury is essential so worsening signs are not missed.
- Concussion = temporary brain-function change after head/neck trauma
- Symptoms may be delayed—observe for hours after injury
- Most recover, but complications can follow if care is delayed or a second hit occurs
- First priorities: safety, breathing, no alcohol, seek medical help
- Avoid aspirin/ibuprofen right after injury unless a clinician advises otherwise—bleeding risk
- No return to sport, driving, or high-risk activity until cleared
What happens in the body
An impact or abrupt acceleration–deceleration can stretch or disrupt brain networks, producing the mixed physical, cognitive, and emotional symptoms of concussion.
Severity concepts often used in education: milder grades with brief symptoms and no loss of consciousness; more severe when symptoms last longer or consciousness is lost, sometimes with amnesia for the event. Regardless of label, medical review is needed.
- Brain motion inside the skull after impact or violent shaking
- Symptoms reflect temporary network dysfunction, not always a visible bruise on scan
- A second concussion before recovery (second-impact risk) can cause dangerous swelling
- Age extremes, bleeding/clotting disorders, anticoagulants, or prior brain surgery raise complication risk
Signs and symptoms
Watch for these signs after a head or neck injury. Seek care promptly if several appear or any red-flag feature is present:
- Memory loss for the injury event (amnesia)
- Headache
- Nausea or vomiting
- Ringing in the ears
- Fatigue, dizziness, or lightheadedness
- Blurry vision
- Confusion or feeling disoriented
- Slowed or delayed speech
- Loss of consciousness (uncommon but serious)
- Irritability or personality change
- Disturbed sleep or forgetfulness
- Sensitivity to light or noise
- Worsening headache, repeated vomiting, or increasing confusion (red flags)
- Fluid or blood from nose or ears (emergency)
Causes and risk factors
Any forceful head or neck trauma can cause concussion. Common situations include:
- Falls, especially in young children and older adults
- Contact or high-risk sports (for example football, boxing, rugby) without adequate protection
- Playing sports without proper helmets or safety gear
- Physical assault or fighting
- Car or motorcycle crashes
- Combat-related blast or impact exposure
- Prior concussion, which raises risk of another
- Workplace or recreational impacts to the head or neck
Diagnosis and evaluation
Clinicians diagnose concussion from history and exam; imaging is used when more serious injury is suspected:
- History of the mechanism of injury and symptom timeline
- Neurological exam: orientation, memory, balance, vision, coordination
- Assessment for red flags suggesting intracranial bleeding or skull injury
- Observation period because symptoms can evolve
- Imaging (CT/MRI) when indicated—not required for every mild concussion
- Review of medications and bleeding/clotting risks
- Guidance on cognitive and physical rest relative to symptom load
Treatment and management
Early care is about protection and medical assessment. Do not improvise invasive or drug treatments at home:
- Assume concussion is possible after significant head injury; move the person to a safer place if the scene is hazardous
- Check that breathing is adequate; call emergency services for severe or worsening signs
- Keep the person still and calm; avoid sudden movements while waiting for help when serious injury is possible
- Do not give alcohol; do not give aspirin or ibuprofen unless a clinician says it is safe
- A cold pack wrapped in cloth may ease local swelling; do not apply ice directly to skin
- For external bleeding from a cut, apply firm pressure with a clean cloth while seeking care
- Medical evaluation for all grades; children with serious head injury need prompt review
- Relative rest from sport, school overload, and driving until symptoms improve and a clinician clears return
Prevention, self-care, and lifestyle
Not every condition is fully preventable, but the steps below may lower risk or recurrence:
- Wear appropriate helmets for sports and cycling
- Use seatbelts; wear motorcycle helmets
- Supervise young children around falls from height
- Reduce home fall hazards such as loose stairs or poor lighting
- Do not return to contact sport until fully cleared after a concussion
Possible complications
Delay, missed care, or unsafe self-medication can raise the chance of complications in some cases:
- Post-concussion syndrome: symptoms lasting beyond about three months
- Post-traumatic headaches continuing more than a week
- Post-traumatic vertigo lasting days to months
- Second-impact syndrome: another concussion before recovery, risking dangerous brain swelling
- Mood changes including anxiety, stress, or depression
- Higher complication risk over age 65 or with bleeding/clotting disorders or anticoagulant drugs
- Risk after prior brain surgery or known clotting tendency
- Delayed recognition leading to missed intracranial injury
When to see a doctor or seek emergency care
Seek prompt medical advice or emergency care if any of the following apply—it is safer not to wait and see:
- Any suspected concussion—especially in children—warrants medical advice
- Loss of consciousness longer than about 30 seconds
- Severe or worsening headache
- Blood or fluid from nose or ears; persistent ear ringing with other neurological signs
- Blurry vision, ongoing confusion, or repeated vomiting
- Seizure, unequal pupils, weakness, or inability to wake the person—emergency care now
- Symptoms lasting days to weeks without improvement—follow-up needed
Living with the condition
After medical clearance for home recovery, prioritise sleep, hydration, and a gradual return to thinking and physical tasks as symptoms allow. Pushing through sport or exams too early can prolong recovery.
Limit stressful situations early on if irritability or anxiety spikes. Friends and family can help by watching for delayed symptoms and supporting a paced return to routine.
Do not drive until coordination and concentration are reliable and a clinician agrees. Athletes should follow a supervised stepwise return-to-play plan to reduce second-impact risk.
Frequently asked questions
Can a concussion be noticed right away?
Often yes, but sometimes symptoms appear later. Monitor for several hours after a head injury even if the person seems normal at first.
What should you do if you suspect a concussion?
Help the person stay still and describe symptoms, avoid unnecessary movement if serious injury is possible, and seek medical care promptly—call emergency services for red-flag signs.
Should someone with a concussion drive?
No. Concussion can impair hand–eye coordination and judgment. Drive only after symptoms settle and a clinician says it is safe.
Are emotional changes common after concussion?
Yes. Stress, anxiety, or low mood can follow. Reducing unnecessary stressors and seeking follow-up if mood changes persist is appropriate.
Is sleeping after a concussion always dangerous?
Wanting to sleep can be normal, but someone should be assessed when red-flag signs are present. Follow clinician advice on observation rather than informal “wake every hour” myths without guidance.
When is return to sport safe?
Only after symptoms resolve with rest and a clinician clears a graded return. Returning too soon raises the risk of another injury and second-impact complications.
Important caution
This guide supports recognition and safe first response; it is not a full emergency-medicine protocol.
When red-flag neurological signs appear, go to emergency care immediately rather than waiting at home.
Recovery plans—including return to school, work, driving, or sport—should follow clinical advice.