Concussion / TBI red flag checklist after an accident
The warning signs that can appear hours or days after a crash
A traffic accident can affect the brain even when there is no direct hit to the head. A sudden stop, violent jolt, or whiplash motion can cause the brain to move inside the skull. This can lead to a concussion or traumatic brain injury, also called TBI. Some symptoms appear right away. Others may show up hours or days later.
After a crash, adrenaline and shock can hide pain, confusion, and other warning signs. A person may say they feel fine even when their body and brain are still reacting to the impact. This is why it is important to watch closely after any accident.
This checklist is not a diagnosis. It is a non-exhaustive safety guide. It is always advised to seek professional medical service promptly. If you see any red flag signs, call 911 or seek emergency medical care right away.
For adults and teenagers age 13 and older, loss of consciousness is a serious warning sign, even if it lasts only a few seconds. Emergency care is also needed if the person becomes more drowsy, has trouble staying awake, seems extremely groggy, or becomes harder to wake.
Severe neck pain after a crash should also be treated seriously. This is especially important if the pain is along the middle of the spine, if the person cannot move the neck normally, or if moving the neck causes pain. A traffic accident can injure both the brain and the neck, so it is safer to be cautious.
Weakness, numbness, tingling, or burning in the arms or legs can be a warning sign of a neurological injury. This is especially concerning if symptoms affect more than one limb or appear on one side of the body.
Changes in the eyes can also signal danger. Get emergency care if one pupil looks larger than the other, if the pupils do not react normally, if the person has double vision, or if there is sudden vision loss.
Speech, balance, and coordination problems should not be ignored. Slurred speech, stumbling, clumsiness, trouble standing, or trouble walking after a crash may point to a serious brain injury.
Repeated vomiting is another red flag. This includes vomiting that continues, becomes forceful, or appears later after the accident. A severe headache that keeps getting worse is also a serious concern, especially if it does not improve with rest.
Visible signs of a serious head injury need urgent attention. These may include a skull deformity, a dent or soft area in the skull, bruising around the eyes, bruising behind the ears, or clear fluid or blood leaking from the nose or ears.
Sudden behavior changes can also be a warning sign. Extreme restlessness, agitation, combativeness, confusion, or unusual aggressive behavior after a crash should be taken seriously.
A seizure, convulsion, abnormal body stiffness, or unusual posturing after a crash is an emergency. Call 911 right away.
Extra caution is needed if the person has a bleeding disorder, takes blood-thinning medicine, or has had prior brain surgery. These factors can increase the risk of serious bleeding after a head injury, even when the crash seems minor.
Children may not be able to explain what they feel after an accident. They may not say they have a headache, dizziness, confusion, or vision changes. Parents and caregivers should watch for changes in behavior, speech, movement, eating, and alertness.
For children ages 2 to 12, emergency care is needed if the child cries continuously and cannot be comforted. A high-pitched or unusual cry after a crash should be treated seriously.
A sudden refusal to eat, drink, or nurse can also be a warning sign. This is especially important if the child normally eats or drinks without trouble.
Extreme drowsiness in a child is another red flag. Get help if the child is difficult to wake, cannot stay awake during normal daytime hours, or seems much sleepier than usual.
Speech changes should also be watched closely. This may include slurred speech, slower speech, trouble finding words, or speaking less clearly than normal.
A child who suddenly becomes clumsy, stumbles, has trouble walking, or loses motor skills they already had should be evaluated right away.
Confusion and memory problems are also important warning signs. This includes not recognizing familiar people or places, repeating questions, acting disoriented, or becoming more confused over time.
Repeated vomiting after a crash is a red flag in children and should be treated as urgent.
Infants cannot describe pain, dizziness, nausea, vision problems, or confusion. Caregivers must look for physical and behavioral changes.
For infants under age 1, emergency care is needed if there is a large bump, soft swelling, or dent on the scalp. This is especially concerning near the side or upper areas of the head.
Breathing changes are also serious. Watch for irregular breathing, long pauses in breathing, or sudden changes in skin color, such as looking pale, gray, or bluish.
Eye changes may also signal a brain injury. These include repeated abnormal eye movements, eyes fixed to one side, or a fixed downward gaze.
An infant who cries when the head or neck is moved, resists being held, or seems unusually sensitive to touch should be checked right away.
Extreme sleepiness, lack of response to familiar voices, or inability to wake the infant is an emergency.
Persistent irritability or extreme crankiness that is very different from the infant’s normal behavior should also be treated seriously.
Some brain injury warning signs do not appear immediately. A person may seem alert after the crash, then develop serious symptoms later. This can happen over hours, days, or even longer.
Seek urgent medical care if a headache becomes worse over time, does not go away, or does not respond to normal care. A worsening headache after a crash should not be dismissed.
Repeated vomiting that is not related to food may also be a warning sign. This is especially concerning if it appears with headache, confusion, weakness, or sleepiness.
One pupil becoming larger than the other is an emergency. So is new weakness, numbness, or tingling on one side of the body.
Slurred speech, worsening confusion, severe memory problems, unusual behavior, or increasing drowsiness should also be treated as urgent.
People who take blood thinners or have bleeding disorders need extra caution. Even a minor head impact can become more serious in these situations.
Not every concussion or TBI looks dramatic at first. Some signs are subtle and easy to blame on stress, soreness, or fatigue.
Pay attention to brain fog, trouble concentrating, slower thinking, memory problems, and difficulty following conversations. These can be signs that the brain is not functioning normally after the crash.
Sensitivity to light or noise can also be a warning sign. A person may feel overwhelmed by bright lights, screens, traffic sounds, music, or normal conversation.
Dizziness, balance problems, nausea, and unusual fatigue should also be monitored. So should new anxiety, irritability, sleep changes, or feeling emotionally unlike yourself.
Neck pain and concussion symptoms can overlap after a traffic accident. A person may assume it is only whiplash, but cognitive changes, memory problems, light sensitivity, and noise sensitivity may point to a brain injury as well.
If any red flag symptom appears, call 911 or go to the nearest emergency department. Do not wait to see if it gets better.
If a spine or neck injury is possible, do not move the person unless there is an immediate danger. Do not remove a helmet or protective gear unless emergency breathing support requires it.
Do not let the person return to driving, sports, work duties, or risky activity the same day if a concussion is suspected.
Do not leave the person alone during the early hours after a suspected brain injury. Watch for delayed or worsening symptoms.
Let the person sleep naturally unless a medical professional gives different instructions. Sleep can support recovery. While the person sleeps, check for normal breathing and normal skin color. Seek emergency help if breathing becomes irregular or if the person cannot be awakened.
A concussion or traumatic brain injury can be easy to miss after a traffic accident. The person may look normal. They may speak clearly. They may even insist they are fine. But symptoms can change as shock wears off.
The safest approach is to watch closely, take symptoms seriously, and get medical help when red flags appear. Brain injuries deserve careful attention. Early action can protect health, recovery, and long term wellbeing.