Head Injury

Medically Reviewed By William C. Lloyd III, MD, FACS

What is a head injury?

Head injury is trauma to any part of your head, including the scalp, skull or brain. Trauma can occur in a variety of situations, such as a car accident or a fall off your bike, or from different sources, such as a bullet wound or shrapnel impact.

Head injuries can be very dangerous and life threatening. Head injuries can also be very deceptive wherein suspected ‘minor trauma’ results in serious medical problems. It is important to note that if you sustain trauma to your head yet feel fine afterward, you could still have a head injury. Some serious head injuries, including concussions, do not produce symptoms that are noticeable immediately. It may be hours before you experience any symptoms. It is important to take any head injury very seriously and seek appropriate medical care.

There are two main types of head injury, open and closed. An open head injury is a trauma in which the skull has been broken and the skin is lacerated. A closed head injury is a trauma in which the head forcibly collides against an object but the skull does not break open. A concussion is a type of closed head injury. Both types of head injuries can be equally life threatening.

Regardless of symptoms, anyone who suffers a strong blow to the head should seek medical care. Examples include head trauma from a high-speed car accident, a high-speed bicycle crash, personal assault, a bullet wound to the head, or a fall from a high place. For head injuries from a low-impact collision, there are still some symptoms that should not be ignored, including a bad headache, loss of consciousness, pupils that are different sizes, memory loss, inability to move a body part, and unexplained anger and irritability, among others.

Seek immediate medical care (call 911) for serious symptoms, such as confusion or loss of consciousness for even a brief moment, an obvious opening or break in the skull, unconsciousness, severe bleeding from the face or head, lethargy, difficulty breathing or not breathing at all, and pain in the back or neck area.

Seek prompt medical care for any significant head trauma, even if the symptoms are mild. Even if no symptoms appear after a blow to the head, that person should be monitored closely to ensure delayed symptoms do not emerge.

What are the symptoms of a head injury?

Symptoms of head injury include pain, bleeding, an obvious wound, inability to control bodily functions, and difficulty with memory, thinking, talking, comprehension or reading.

Common symptoms of a head injury

You may experience head injury symptoms daily or only occasionally. Any of these head injury symptoms can be severe:

  • Abnormal noises, bells, whooshing sounds

  • Abrupt changes in personality, such as anger or irritability, without an apparent cause

  • Bone fractures or deformity, especially of the skull or face

  • Clear or blood-tinged fluid coming from the mouth, ears or nose

  • Confusion; drowsiness; clumsiness; memory loss; lethargy; or trouble speaking, seeing or hearing

  • Difficulty standing or walking

  • Droopy eyelid

  • Loss of control of bodily functions

  • Pupils that are different sizes, or pupils that do not change when exposed to light and dark

  • Seizure or unexplained shaking or convulsions

  • Severe headache

  • Slow or stopped breathing

  • Unconsciousness and coma

  • Vision problems (double vision, decreased vision)

  • Vomiting

  • Weakness (loss of strength) or paralysis

Serious symptoms that might indicate a life-threatening condition

In many cases, head injuries can be life threatening. Seek immediate medical care (call 911) if you, or someone you are with, have any of these life-threatening symptoms including:

  • Abnormal pupil size or reactivity to light

  • Abrupt confusion, fatigue, changes in thinking, or lethargy soon after a head trauma

  • Deformity or fracture of bones

  • Multiple unexplained episodes of vomiting after a head trauma

  • Neck or back injury

  • Paralysis or severe muscle weakness (especially face and extremities)

  • Seizures

  • Severe bleeding from the head or face, especially if the wound is deep

  • Slowed or stopped breathing

  • Unconsciousness (even if brief)

What causes a head injury?

A head injury is any trauma to the head or face. It is caused by a forcible collision with some sort of object, large or small, such as the ground, a car, or a bullet. Some head injuries result in a break in the head or a fractured skull, which can immediately cause brain damage. Other head injuries result in swelling, which can damage the brain as the swelling progresses.

What are the risk factors for a head injury?

A number of factors increase the risk of developing head injury. Not all people with risk factors will get head injury. Risk factors include:

  • Alcohol or illicit drug use

  • Driving while intoxicated

  • Driving without seatbelts

  • Occupational activities

  • Participation in sports, especially without the proper safety gear

Reducing your risk of a head injury

While it is not possible to completely eliminate the risk of a head injury, there are some common sense ways that you can reduce your risk of a head injury. You may be able to lower your risk of head injury by:

  • Never drinking and driving

  • Obeying the speed limit and traffic signs, whether in a car or on a bike

  • Using a proper car seat when transporting infants and young children

  • Watching children while they play

  • Wearing a helmet, other safety equipment, and bright and reflective clothing whenever you bike, rollerblade or skateboard

How is a head injury treated?

Treatment for a head injury depends on its severity and exact location or type. A mild head injury can be treated by careful observation to monitor any worsening of symptoms and by medications, such as acetaminophen (Tylenol), to control headache. Moderate or severe head injuries are treated with supportive care to ensure adequate oxygen and proper blood flow to the brain, among other things. Additionally, it is important to limit swelling in the brain. In severe head injuries, the skull may have to be partially removed to allow the brain room to expand. Surgery may also be needed to repair damaged vessels or other tissues in the brain or around the skull.

Because head injuries vary so widely in severity, location and prognosis, it is most important to work with your health care provider immediately to treat any moderate or severe head injury.

What are the potential complications of a head injury?

Head injury, especially a moderate or severe injury, can have a wide variety of complications, many of which can be life threatening. You can help minimize your risk of serious complications by following the treatment plan you and your health care professional design specifically for you. Complications of head injury include:

  • Brain death
  • Cardiac arrest
  • Coma
  • Memory loss
  • Paralysis
  • Permanent disability
  • Respiratory arrest
  • Speech problems
  • Stroke
  • Vegetative state
  • Weakness (loss of strength)
Was this helpful?
  1. Head injury – first aid. Medline Plus, a service of the National Library of Medicine National Institutes of Health. http://www.nlm.nih.gov/medlineplus/ency/article/000028.htm
  2. NINDS traumatic brain injury information page. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/tbi/tbi.htm
  3. Collins RD. Differential Diagnosis in Primary Care, 5th ed. Philadelphia: Lippincott, Williams & Williams, 2012.
  4. Domino FJ (Ed.) Five Minute Clinical Consult. Philadelphia: Lippincott Williams & Wilkins, 2013.
Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 Jan 18
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.