Concussion in Sport: What to Do in the First 48 Hours
Concussion is one of the few sports injuries where what happens in the first hour matters as much as anything that follows. It is also one of the most misunderstood, largely because the two things people most associate with it — losing consciousness, and something showing up on a scan — are both usually absent.
What a concussion is
Concussion is a functional injury to the brain caused by a force transmitted to the head. That force does not have to be a direct blow to the head; a heavy impact to the body that whips the head and neck can do it.
The key word is functional. The injury is to how the brain is working, not to its structure, which is why a CT or MRI scan is typically normal in concussion. A normal scan does not mean a concussion has not happened. Scans in this setting are used to rule out more serious structural injury, such as a bleed, rather than to diagnose the concussion itself.
The majority of concussions involve no loss of consciousness at all. Waiting for someone to be knocked out before taking it seriously means missing most of them.
What to do immediately
Anyone with a suspected concussion should be removed from play and should not return to play that day. That applies regardless of how well they say they feel, how important the fixture is, or how quickly the initial symptoms settle. The old approach of a brief assessment on the sideline followed by a return to the pitch is no longer considered acceptable practice.
The reason is straightforward. Symptoms often evolve over the following hours, and a second impact before recovery carries disproportionate risk.
Signs that should prompt removal include appearing dazed or blank, unsteadiness, slowed responses, difficulty remembering the passage of play, headache, nausea, dizziness, or sensitivity to light or noise. Anything that seems out of character for that person is worth taking seriously.
Symptoms that need emergency assessment
Most concussions do not require a hospital visit. The following do, and urgently:
A headache that is severe or steadily worsening
Repeated vomiting
A seizure or convulsion
Weakness, numbness or tingling in the arms or legs
Slurred speech, double vision, or difficulty walking
Increasing confusion, agitation or unusual behaviour
Becoming drowsy or difficult to rouse
Significant neck pain or tenderness
Neck pain after a head impact should be treated as a potential neck injury until it has been properly assessed. See Neck and Spine Pain.
The first 24 to 48 hours
Current guidance has moved away from prolonged complete rest in a darkened room, which was standard advice for years and is now understood to slow recovery rather than help it.
A relative rest period of roughly 24 to 48 hours is appropriate: reduced screen time, no training, no driving, no alcohol, and avoiding anything that meaningfully worsens symptoms. After that, light activity such as walking can usually be reintroduced gradually, guided by symptoms rather than by the calendar.
The person should not be left alone for the first several hours, and someone should know what the red-flag symptoms are.
Returning to activity
Return to sport follows a stepwise progression, moving from light aerobic exercise through sport-specific work and non-contact training before any return to full contact. Each step is symptom-limited, and a return of symptoms means dropping back a stage.
Importantly, return to work or study comes before return to contact sport. Someone who cannot yet concentrate through a normal working day or a full day of school is not ready to be tackled.
Children and adolescents are managed more conservatively than adults, with a slower progression.
The final return to contact should follow clinical clearance rather than a self-assessment, and that is particularly true for anyone with a history of previous concussions, a recovery that has taken longer than expected, or symptoms that keep recurring on exertion.
When recovery is not straightforward
Most people recover within a few weeks. A minority have symptoms that persist beyond that, and these are worth assessing properly rather than waiting out — persistent symptoms after concussion are often driven by several separate and treatable factors, including neck involvement, visual and vestibular problems, sleep disruption, exercise intolerance and mood changes.
Each of those responds to different management, which is why a general instruction to rest and hope is rarely the right answer at that stage.
This information is educational and does not replace an individual medical assessment. Anyone with a suspected concussion should be assessed by a qualified clinician.