Head Injury: What to Do and When to Worry

First aid for a head injury

1. Check responsiveness and breathing. If the person is unresponsive or not breathing normally, call 911 and start CPR if trained.
2. Keep the head and neck still if a spine injury is possible (fall from height, diving, crash, neck pain). Do not remove a helmet unless needed for breathing.
3. Control scalp bleeding with firm pressure using a clean cloth. Scalp wounds bleed heavily. If you suspect a skull fracture, press gently around the edges, not on it.
4. Apply a cold pack wrapped in a cloth to swelling for 20 minutes.
5. Watch closely for danger signs for at least 24 hours. Someone should stay with the injured person.
6. Pain relief: acetaminophen (paracetamol) is preferred. Avoid aspirin and, for the first day, ibuprofen, which can increase bleeding risk.

Types of head injury

Symptoms

Minor head injury and concussion

• headache
• dizziness or balance problems
• nausea, vomiting once
• feeling dazed, foggy or slowed down
• confusion or memory gaps about the event
• sensitivity to light and noise
• blurred vision
• irritability, emotional changes, sleep problems

Symptoms may appear immediately or develop over hours.

Signs of a brain bleed or serious injury

• worsening headache
• repeated vomiting
• increasing drowsiness or confusion
• seizures
• weakness, numbness or trouble speaking
• unequal pupils
• loss of consciousness

Infants and young children

Children may not describe symptoms. Watch for persistent crying, irritability, changes in feeding or sleep, loss of interest in play, vomiting, a bulging soft spot, or a large swelling, especially on the side or back of the head in babies under 1 year.

Who needs a CT scan?

Doctors use clinical decision rules (such as the Canadian CT Head Rule for adults and PECARN for children) to decide who needs a CT scan. CT is usually recommended for:

• loss of consciousness with other risk factors, or amnesia
• confusion or a low score on the Glasgow Coma Scale
• vomiting more than once
• suspected skull fracture
• seizure
• age 65 or older with any loss of consciousness or amnesia
• blood thinners
• a dangerous mechanism of injury
• focal neurological signs

Many people with mild injuries do not need a scan. A normal CT does not rule out concussion, which is a functional, not structural, injury.

Treatment

Minor injuries and concussion

• Relative rest for 24 to 48 hours: limit screens and demanding mental activity, but light activity such as walking is encouraged.
• Gradual return to school, work and exercise as symptoms allow.
• No contact sports or high-risk activities until fully recovered and cleared by a clinician.
• Avoid alcohol and sedatives until recovered.
• Sleep: it is fine to sleep after a head injury once a clinician has assessed it; waking every hour is no longer routinely advised, unless instructed.

Return to sport

A stepwise return-to-play protocol, usually over at least a week after symptoms resolve: light aerobic exercise, sport-specific drills, non-contact training, full contact practice, then competition, moving to the next step only if symptom-free. Never return to play on the same day as a suspected concussion.

Serious injuries

Hospital care may include observation, surgery to remove blood clots or relieve pressure, intensive care, and later rehabilitation.

Complications

• post-concussion syndrome: headaches, dizziness, fatigue, poor concentration and mood changes lasting beyond a few weeks
• chronic subdural hematoma developing weeks later, especially in older adults
• post-traumatic epilepsy
• long-term cognitive, emotional and physical disability after moderate to severe TBI
• second impact syndrome: rare, dangerous brain swelling from a second concussion before recovery, mainly in young athletes

Prevention

• wear helmets for cycling, skiing, skating, horse riding, motorcycling and contact sports
• always wear seatbelts and use correct child car seats
• prevent falls in older adults: remove trip hazards, improve lighting, install grab bars, review medicines, do strength and balance exercises
• install window guards and stair gates for young children

Frequently asked questions

When should I go to the ER after hitting my head?

Go to the ER or call 911 for loss of consciousness, repeated vomiting, worsening headache, confusion, seizures, weakness, slurred speech, fluid from the nose or ears, or if you take blood thinners or are over 65. A mild bump without these signs can usually be watched at home.

What are the signs of a brain bleed after hitting your head?

Warning signs include a headache that keeps getting worse, repeated vomiting, increasing sleepiness or confusion, weakness or numbness on one side, slurred speech, unequal pupils and seizures. These can develop hours later, so watch for 24 hours after an injury.

Is it safe to sleep after a head injury?

Yes, in most cases, once the person has been assessed and has no danger signs. Sleep helps recovery. Someone should check on them and seek help if they are hard to wake, confused or develop new symptoms.

How long does a concussion take to heal?

Most people recover within 2 to 4 weeks, children and teens sometimes taking a little longer. Gradual return to normal activity helps. Symptoms lasting longer may be post-concussion syndrome and benefit from specialist rehabilitation.

When should I worry about a child's head injury?

Seek emergency care if a child loses consciousness, vomits repeatedly, seems confused or very sleepy, has a seizure, cannot stop crying, has a bulging soft spot or a large swelling on the head, or is not acting normally. Infants under 1 year with significant bumps should be checked.