U.S. flag An official website of the United States government
  1. Home
  2. For Consumers
  3. Consumer Updates
  4. Traumatic Brain Injury: What to Know About Symptoms, Diagnosis, and Treatment
  1. Consumer Updates

Traumatic Brain Injury: What to Know About Symptoms, Diagnosis, and Treatment

Traumatic brain injury (TBI) can happen in a variety of situations. And everyone is at risk, especially children and older adults.

Collage of four photos showing the aftermath of a serious car accident, armed soldiers in the field wearing full combat gear and helicopters flying in the background, football players colliding violently, an older women bracing herself nervously at the top of the stairs


A car accident. A football tackle. An unfortunate fall. These things—and more—can cause head injuries. Head injuries can happen to anyone, at any age, and they can damage the brain.

Here’s how damage can happen: A sudden movement of the head and brain can cause the brain to bounce or twist in the skull, injuring brain cells, breaking blood vessels, and creating chemical changes. This damage is called a traumatic brain injury (TBI).

The U.S. Food and Drug Administration continues to study TBI and encourages the development of medical devices to help diagnose and treat it.

Causes and Symptoms of TBI

TBI is often caused by a bump, blow, jolt, or explosive blast to the head, or a penetrating head injury that disrupts the brain’s normal function. Not all hits to the head result in TBI. But when it happens, TBI can range from mild (like a brief change in mental status or consciousness) to severe (like a longer period of unconsciousness or major problems with thinking and behavior after injury).

About 75 percent of TBIs (or 3 out of every 4) that occur each year are mild. If a person has the symptoms of TBI after a blow to the head, then the brain has been injured. Mild TBIs always involve some degree of brain injury.

Symptoms of mild TBI include:

  • headache
  • confusion
  • dizziness
  • ringing in the ears
  • memory impairment
  • blurred vision
  • behavioral changes

Moderate and severe TBI can produce more symptoms including:

  • repeated vomiting or nausea
  • slurred speech
  • weakness in the arms or legs
  • problems with thinking and learning
  • death

If you have questions about TBI, talk to your health care provider. Anyone with signs of TBI should receive medical attention as soon as possible. Call 911 in emergency situations.

Diagnosis of TBI

While some symptoms of mild TBI can be hard to detect, the Centers for Disease Control and Prevention (CDC), the American College of Rehabilitation Medicine, and some others have published guidelines for diagnosing TBI.

A medical exam is the first step to diagnose a potential brain injury. Assessment usually includes a neurological exam. This exam evaluates thinking, motor function (movement), sensory function, coordination, eye movement, and reflexes.

Imaging tests, including CT scans and MRI scans, cannot detect all TBIs. But tests from these FDA-regulated medical devices can help health care providers rule out some of the more serious brain injuries. In particular, these scans can detect bleeding that resulted from the traumatic injury which requires immediate medical or surgical attention.

None of the medical devices cleared or approved by FDA are intended to be used alone without the judgment of a health care provider trained to diagnose and treat TBI. The FDA has not cleared or approved any medical products that are intended to diagnose or treat TBI alone without other diagnostic tests or treatments managed by a health care provider.

Important safety note: The FDA  issued a safety communication in 2019 that includes recommendations and warnings against the use of medical devices that have not been FDA-approved or FDA-cleared for the assessment, diagnosis, or management of a head injury or “concussion,” another name for mild traumatic brain injury.

Medical devices that are not FDA-approved or FDA-cleared may not correctly diagnose a TBI. FDA-approved and FDA-cleared devices may not correctly diagnose a TBI if used alone without other diagnostic tests managed by a healthcare provider. An incorrect diagnosis may lead to:

  • A wrong decision to let a person return to play or other activities with a brain injury
  • A missed diagnosis of brain injury, or
  • The lack of proper treatment for a head injury

If you have a head injury, seek medical attention right away. The FDA has not approved any devices that can assess or diagnose a traumatic brain injury without an evaluation by a health care provider.

More FDA Actions and Research on TBI

The FDA continues to work with the research and clinical community to develop better-designed clinical studies so new medical products can be developed. And the FDA continues to review and evaluate medical devices for safety and effectiveness.

More sensitive and objective ways to diagnose and detect mild TBI are needed. Timely diagnosis is important to prevent repetitive injury and to help develop new therapies. That’s because repetitive injury carries the risk of “second impact syndrome.” If people who have not recovered from a head injury have a second head injury, this can result in more significant injury to the brain and more neurological deficits.  And, in some cases, repetitive injury can be fatal or cause dementia later in life.

The FDA’s scientists continue to conduct research on diagnostic tests for mild TBI. The scientists are studying TBI blood tests, special brain imaging, eye movements, and brain wave patterns. They are also investigating using portable imaging devices to detect mild TBI.

What to Know About the Effects of TBI

Little can be done to reverse initial brain damage caused by trauma according to the National Institute of Neurological Disorders and Stroke. But health care professionals will work to stabilize patients and try to prevent further harm. The severity of long-term effects depends on the seriousness of the injury, location of the injury, the number of previous brain injuries, and the age and general health of a patient.

Helping Protect Athletes’ Brains from Repeated Minor Impacts to the Head

In early 2021, the FDA authorized marketing of a device to aid in the protection of the brain from effects associated with repeated minor impacts to the head seen on special MRI scans.

The device, called the Q-Collar, is intended for athletes aged 13 years and older. The device should be used with other protective sports equipment, which it does not replace. The Q-Collar does not require a prescription.  Use has not been shown to allow for more rapid return to TBI risk activities or to allow for undertaking activities with increased risk of TBI or use of increased force during sports activities.

Remember, if you have any have questions about a possible brain injury, please talk with your health care provider.

Consumer Updates Email

Subscribe to receive Consumer Updates email notifications.

Back to Top