Immediate Signs and Symptoms of Concussion
The immediate signs and symptoms of concussion include headache, nausea, impaired balance, difficulties concentrating, confusion, emotional lability, and fatigue, with loss of consciousness occurring in only a minority of cases. 1
Core Immediate Signs (Within First 24 Hours)
The most prevalent and consistent indicators of acute concussion that should prompt immediate removal from activity include:
Physical Signs
- Headache (most common symptom in both adults and children) 2
- Nausea and vomiting 3, 1
- Dizziness and impaired balance (documented within 1 day after injury) 3, 4
- Blurred vision or visual disturbances 3, 1
- Loss of consciousness (occurs in only 22% of cases, and if lasting >30 seconds suggests more significant injury) 5, 6
- Convulsions or tonic posturing 7
Cognitive and Behavioral Signs
- Confusion and disorientation (observed immediately after the event) 3, 4, 7
- Memory problems - both retrograde and anterograde amnesia 3, 8
- Difficulty concentrating or paying attention 3, 1
- Feeling "in a fog" or not feeling right 7
- Slower reaction time (within 2 days after injury) 4
- Impaired verbal learning and memory (within 2 days after injury) 4
Neurological Signs
- Ataxia (loss of balance and coordination) 7
- Visual trouble 7
- Neurological deficits 7
- Sensitivity to light (photophobia) and/or noise 3, 2
Emotional/Behavioral Changes
Critical Warning Signs Requiring Emergency Activation
Activate EMS immediately if any of the following severe signs develop: 1
- Loss of consciousness
- Worsening or severe headache
- Repeated vomiting
- Altered mental status
- Seizures
- Visual changes
- Swelling or deformities of the scalp
- Focal neurological deficits
- Increased sleepiness or passing out
- Abnormal behavior
These signs are associated with increased risk of life-threatening intracranial pathology including epidural hematoma, subdural hematoma, open skull fracture, or brain edema. 1
Important Clinical Pitfalls
Loss of consciousness is NOT required for concussion diagnosis - the majority of concussions occur without loss of consciousness or frank neurological signs. 5, 9 Only approximately 15-22% of concussions involve loss of consciousness. 5, 6
Symptoms evolve over time - some signs and symptoms may not appear immediately but develop over minutes to hours after the injury. 10 The acute symptoms are typically most severe within the first 24-48 hours post-injury. 9
Memory and cognitive problems are highly predictive - immediate recall problems and memory deficits are strong predictors of more significant injury requiring removal from activity. 11 Documented disorientation or confusion immediately after the event is one of the most prevalent and consistent indicators. 4
The number of symptoms matters - a higher number of initial signs and symptoms correlates with more severe injury and predicts removal from play or hospitalization. 11