Concussion is a clinical diagnosis defined by the acute onset of neurological symptoms—physical, cognitive, emotional, and sleep-related—following direct or indirect traumatic force to the head, resulting in transient shear stress to brain tissue. [1-2] Headache is the most common symptom. Most patients recover within 2–4 weeks, though approximately one-third of untreated adolescents may have symptoms persisting beyond 4 weeks. [3-4]
1. History
- Mechanism of injury: Direct blow vs. indirect force (whiplash, blast); determine intensity (fall height, collision speed, ejection from vehicle) [5]
- Temporal relationship: Symptom onset immediately or within minutes to hours of injury; symptoms may evolve over days [2][5]
- Symptom characterization: Headache (most common), pressure in head, dizziness, nausea, light/noise sensitivity, feeling "foggy," difficulty concentrating, fatigue, visual disturbance, emotional lability [5-6]
- Loss of consciousness (LOC): Duration (brief vs. >30 seconds); LOC is not required for diagnosis [1][7]
- Amnesia: Retrograde (events before injury) and anterograde (events after); duration matters for CT decision rules [7-8]
- Important negatives: Seizure activity, neck pain, vomiting, worsening headache, anticoagulant use, prior concussions, pre-existing migraine or psychiatric history [9-10]
2. Alarm Features
- GCS <15 at 2 hours post-injury [7][11]
- Suspected open or depressed skull fracture [7]
- Signs of basilar skull fracture: raccoon eyes, Battle sign, hemotympanum, CSF otorrhea/rhinorrhea [7-8]
- Repeated vomiting (≥2 episodes) [7-8]
- Seizure post-injury [12]
- Focal neurological deficit [11]
- Deteriorating level of consciousness [12]
- Severe or worsening headache [12]
- LOC >30 seconds [12]
- Coagulopathy or anticoagulant use [11][13]
- Dangerous mechanism (pedestrian struck, ejection from vehicle, fall >3 ft or >5 stairs) [13]
3. Medications
Acute symptom management (no concussion-specific medications exist): [12]
- Headache: Acetaminophen and NSAIDs (ibuprofen, naproxen) as first-line abortive therapy; limit use to <10 days/month to avoid medication-overuse headache [9][14]
- Migraine-like headache: Triptans (sumatriptan, rizatriptan) if OTC analgesics fail [9][14]
- Nausea: Ondansetron commonly used in the ED [12]
- Sleep disturbance: Melatonin is commonly recommended though evidence is limited; sleep hygiene counseling is first-line [8][15]
- Prophylactic headache therapy (if >10 headache days/month): Amitriptyline, propranolol, candesartan, topiramate, or venlafaxine [9][14][16]
Medications to avoid: Opioids, barbiturates, oral ergot alkaloids. [14] Chronic NSAID/acetaminophen use is discouraged due to rebound headache risk. [9][12]
4. Diet
- Hydration: Maintain adequate fluid intake; dehydration may exacerbate headache and cognitive symptoms [9]
- Regular meals: No skipped or delayed meals; irregular eating may worsen headache [9]
- Alcohol avoidance: Recommended during recovery; alcohol may impair neurological recovery and exacerbate symptoms [9][17]
- Omega-3 fatty acids (DHA/EPA): Strongest emerging evidence supports potential neuroprotective benefit, particularly prophylactically in athletes exposed to repetitive head impacts; however, no definitive human clinical trial evidence yet supports routine use for treatment [18-20]
- Whole food diet: Rich in antioxidants, micronutrients, and fiber is generally recommended for brain health during recovery [17]
- Caffeine: Use cautiously; may contribute to medication-overuse headache patterns [9]
5. Review of Systems
- Neurological: Headache, dizziness, visual changes, photophobia, phonophobia, tinnitus, numbness/tingling
- Cognitive: Difficulty concentrating, memory problems, mental fog, slowed processing [5]
- Emotional/Behavioral: Irritability, sadness, anxiety, emotional lability [1][3]
- Sleep: Insomnia, hypersomnia, difficulty falling asleep, fatigue [1-2]
- Vestibular: Vertigo, motion sensitivity, balance problems [5][21]
- Cervical: Neck pain, stiffness (cervical injury frequently coexists) [3][12]
- Constitutional: Fatigue, drowsiness [5]
6. Collateral History and Family History
- Bystander report: Witnessed LOC, confusion, blank stare, stumbling gait, lying motionless, seizure activity [5]
- Prior concussion history: Number, timing, and recovery duration of previous concussions; history of prolonged recovery [1][9]
- Pre-existing conditions: Migraine, ADHD, learning disabilities, anxiety/depression, sleep disorders [9-10]
- Family history: Migraine, psychiatric disorders, sudden cardiac events (if ECG abnormalities noted) [22]
- Social context: Sport type and level, academic demands, psychosocial stressors, substance use [3][9]
7. Risk Factors
For concussion
- Contact/collision sports (football, hockey, rugby, soccer) [1]
- Prior concussion history (strongest risk factor for future concussion) [1]
- Female sex (higher symptom reporting) [9]
- Youth and adolescent age [12]
For persisting symptoms (>4 weeks)
- High initial symptom burden (strongest predictor) [3][9]
- Pre-existing psychiatric history (anxiety, depression) [9-10]
- Prior concussions/TBIs [9]
- Female sex [9-10]
- Migraine history [9-10]
- Neck pain at presentation [10]
- Pre-existing sleep problems [10]
- Pessimistic recovery expectations, fearful avoidance of activity [9]
8. Differential Diagnosis
- Intracranial hemorrhage (epidural, subdural, subarachnoid, intraparenchymal): Cannot-miss; <10% of mTBI have CT abnormalities, ~1% require neurosurgery [8]
- Skull fracture (open, depressed, basilar) [7]
- Cervical spine injury: Frequently coexists; produces overlapping symptoms (dizziness, headache) [3][12]
- Vestibular injury (BPPV, labyrinthine concussion) [21]
- Migraine (with or without aura): May be triggered by or mimic concussion [3]
- Syncope/cardiac arrhythmia: Consider if LOC preceded the fall [7]
- Seizure disorder: Primary seizure vs. post-traumatic seizure [7]
- Malingering/symptom exaggeration: Particularly in medicolegal or sport contexts
- Anxiety/panic disorder: Symptoms overlap significantly with post-concussive symptoms [3]
- Cervicogenic headache: From concomitant whiplash injury [3][12]
9. Past Medical History
- Previous concussions (number, timing, recovery duration) [1][9]
- Migraine or chronic headache history [9-10]
- Psychiatric history: anxiety, depression, PTSD [9-10]
- Learning disabilities, ADHD [9]
- Sleep disorders [10]
- Anticoagulant/antiplatelet use [11][13]
- Prior neurosurgery or intracranial pathology
- Chronic medical conditions affecting recovery (e.g., chronic pain syndromes)
10. Physical Exam
Vital signs: Heart rate, blood pressure (autonomic dysfunction may cause transient elevations) [23]
Focused exam
- Neurological: GCS, cranial nerves, pupillary response, motor/sensory exam, coordination (finger-to-nose), gait assessment [5]
- Cervical spine: Palpation for tenderness, range of motion, spurling test [3]
- Balance: Modified Balance Error Scoring System (mBESS)—tandem stance, single-leg stance with eyes closed for 20 seconds [5]
- Vestibular-oculomotor: Smooth pursuits, saccades, near-point convergence, vestibulo-ocular reflex (VOR); abnormalities suggest vestibular-oculomotor dysfunction [5]
- Cognitive screening: Orientation, immediate memory (word list recall), concentration (digits backward, months in reverse), delayed recall (SAC) [5][24]
- Scalp/skull: Palpation for hematoma, lacerations, step-off deformity, signs of basilar fracture [7]
Observable signs of concussion: Lying motionless after injury, stumbling gait, blank/vacant stare, disorientation, confusion [5]
11. Lab Studies
- Routine labs are generally not indicated for uncomplicated concussion [3]
- Coagulation studies (INR, platelet count): If on anticoagulants/antiplatelets or suspected coagulopathy [11][13]
- Blood glucose: Rule out hypoglycemia as contributor to altered mental status
- Blood alcohol level/toxicology screen: If intoxication suspected (affects clinical assessment) [8]
- Serum biomarkers (GFAP, UCH-L1): FDA-cleared to help determine need for CT in adults; however, guidelines currently recommend against routine clinical use for concussion diagnosis [2-3]
- hs-CRP: Limited evidence for predicting post-concussion syndrome; not recommended routinely [7]
12. Imaging
CT head (non-contrast) is the imaging modality of choice in the ED: [8]
- Not routinely indicated for concussion; <10% of mTBI patients have CT abnormalities [3][8]
- Use validated clinical decision rules to determine need:
- Canadian CT Head Rule (CCHR): High-risk criteria (GCS <15 at 2 hours, suspected skull fracture, basilar fracture signs, ≥2 vomiting episodes, age ≥65) and medium-risk criteria (retrograde amnesia ≥30 min, dangerous mechanism); 100% sensitivity for neurosurgical lesions with 76% specificity [7-8]
- New Orleans Criteria (NOC): Headache, vomiting, age >60, intoxication, short-term memory deficit, trauma above clavicles, seizure; 100% sensitivity but only 25% specificity [7-8]
- PECARN (pediatric): For children <18 years [12]
MRI: Not indicated acutely; consider if symptoms persist >2 weeks with risk factors for neurosurgical lesion, or for evaluation of repetitive concussions. [8] Can identify hemorrhagic axonal injury not seen on CT. [8]
When imaging is unnecessary: GCS 15, no high- or medium-risk features on validated decision rules, normal neurological exam [3][13]
13. Special Tests
- SCAT6 (ages ≥13) / Child SCAT6 (ages 8–12): Standardized multimodal sideline assessment tool; includes symptom checklist, SAC cognitive screen, mBESS balance testing, neurological screen; takes ≥10 minutes; most accurate within 72 hours of injury [5][25]
- SCOAT6 / Child SCOAT6: Office-based assessment tool for evaluations >72 hours post-injury; guides ongoing management [3][5]
- mSIT Plus (mini Symptom Index Tool + modified VOMS): 6-question symptom tool with vestibular-oculomotor screening; AUC 0.94, sensitivity 88%, specificity 92%; can be completed in 2–3 minutes [6]
- Vestibular/Ocular Motor Screening (VOMS): Assesses smooth pursuits, saccades, near-point convergence, VOR; abnormalities beyond 10 days warrant vestibular PT referral [3][6]
- King-Devick Test: Rapid number naming test assessing saccadic eye movements
- ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing): Computerized neurocognitive testing; most useful with baseline comparison
14. ECG
ECG is not part of routine concussion evaluation but may be relevant in specific scenarios:
- Concussion can cause transient cardiovascular autonomic dysfunction: elevated resting heart rate and blood pressure within 48 hours, typically resolving within 24–48 hours [23][26]
- QTc prolongation has been reported after mild head trauma in pediatric patients; self-limiting but warrants awareness [22]
- ECG changes in severe TBI include ST-segment changes, T-wave inversions, "cerebral" T waves, and QT prolongation [27-28]
- Consider ECG if: syncope preceded the fall (to evaluate for arrhythmia as cause), irregular heart rhythm on exam, or chest trauma coexists [22]
15. Assessment
Clinical summary: Concussion is a clinical diagnosis based on temporal relationship between an appropriate mechanism and symptom onset. No single symptom, sign, or test definitively rules in or excludes concussion. [1][5]
Severity stratification
- The strongest predictor of prolonged recovery is the initial symptom burden (number and severity) [3][9]
- Most patients recover within 2–4 weeks [2][4]
- ~10–20% of adults and ~33% of untreated adolescents develop persisting symptoms (>4 weeks) [3][29]
Typical vs. atypical presentations
- Typical: Headache, dizziness, cognitive fog, fatigue, light/noise sensitivity
- Atypical: Predominantly emotional symptoms, isolated sleep disturbance, delayed symptom onset (hours after injury)
- Symptoms may overlap with pre-existing conditions (migraine, anxiety) [3]
Complications: Persisting post-concussion symptoms, second impact syndrome (rare, catastrophic—primarily in adolescents), chronic traumatic encephalopathy (CTE, associated with repetitive head impacts over years) [1][3]
16. Treatment Plan
Initial management (first 24–48 hours)
- Relative rest (not strict "cocooning"): Reduced activities of daily living, limited screen time [9][25]
- Light-intensity physical activity (e.g., walking) is encouraged even within the first 24–48 hours, as tolerated, to a level that does not more than mildly exacerbate symptoms [9][25]
- Symptom-limited aerobic exercise early after injury reduces the incidence of persisting symptoms [3]
Symptom management
- Acetaminophen or ibuprofen for headache (avoid chronic use) [9][12]
- Sleep hygiene counseling; melatonin may be considered [8][15]
- Antiemetics for nausea as needed [12]
- Cervical physical therapy if cervicogenic component identified [3][12]
- Vestibular rehabilitation for persistent dizziness/balance problems [12][21]
Graduated return to activity: [12][25]
- Symptom-limited activity (24–48 hours post-injury)
- Light aerobic exercise (walking, stationary cycling)
- Sport-specific exercise (no contact)
- Non-contact training drills
- Full-contact practice (after medical clearance)
- Return to competition
Each step requires minimum 24 hours; advance only if symptoms do not worsen more than mildly (≤2-point increase on 0–10 scale, resolving within 1 hour). [9][25] Full return to school/learn should precede unrestricted return to sport. [4][30]
Persisting symptoms (>4 weeks): Referral to multidisciplinary concussion specialist; consider targeted therapies—vestibular PT, vision therapy, cognitive behavioral therapy, cognitive rehabilitation, pharmacologic headache prophylaxis [3][21][29]
The following figure summarizes the evidence for pharmacological interventions in mTBI, stratified by timing and age:
17. Disposition
Discharge criteria (majority of concussions)
- GCS 15 with improving or stable symptoms
- Normal neurological exam
- CT not indicated or CT negative
- Reliable companion available for home observation [8]
- Patient/family educated on return precautions
Admission/observation criteria
- GCS <15 or not improving to 15 within 2 hours [7]
- Abnormal CT findings (intracranial hemorrhage, fracture) [8]
- Persistent vomiting, worsening symptoms, or neurological deterioration [8]
- Anticoagulant use with positive CT or high-risk features [13]
- No reliable home observation available
- Intoxication precluding adequate assessment [8]
Specialist consultation triggers
- Symptoms persisting >4 weeks → concussion specialist/multidisciplinary team [3][9]
- Abnormal vestibular-oculomotor findings beyond 10 days → vestibular PT [3]
- Significant mood/anxiety symptoms → mental health referral [9]
- Abnormal CT → neurosurgery consultation [8]
18. Follow-Up / Return Precautions
Follow-up timing
- Early medical follow-up within 1 week of injury, then weekly, facilitates recovery [3]
- At-risk patients (high symptom burden, psychiatric comorbidity) may benefit from weekly visits over the first month [9]
Return precautions (provide written instructions): [8]
- Return immediately for: worsening headache, repeated vomiting, increasing confusion or drowsiness, seizure, weakness or numbness in extremities, slurred speech, unequal pupils, inability to recognize people/places, unusual behavior, loss of consciousness
- Companion should monitor for first 24 hours; wake patient every 2–4 hours overnight to check for deterioration [8]
Patient counseling
- Most concussions resolve within 2–4 weeks; reassurance and education improve outcomes [1][3]
- Avoid contact sports, high-risk activities, and driving until medically cleared [25]
- Avoid alcohol and recreational drugs during recovery [9]
- Prolonged strict rest is counterproductive; gradual return to activity is beneficial [3][9]
- Academic accommodations (extra time, reduced workload, breaks) may be needed; a provider letter facilitates this [3][9]
Expected recovery: Median symptom-free by ~14 days; return to school ~8 days; unrestricted return to sport typically within 1 month (~20 days average). [3][25]
The following table summarizes current guideline consensus on concussion management:
References
1. Current Concepts in Concussion: Initial Evaluation and Management. — Scorza KA, Cole W. American Family Physician. 2019.
2. Diagnosis and Management of Concussion. — Reams N. Clinics in Sports Medicine. 2026.
3. Sport-Related Concussion. — Leddy JJ. The New England Journal of Medicine. 2025.
4. Selected Issues in Sport-Related Concussion (SRC | Mild Traumatic Brain Injury) for the Team Physician: A Consensus Statement. — Herring S, Kibler WB, Putukian M, et al. Current Sports Medicine Reports. 2021.
5. Does This Child Have a Concussion?. — Shah SN, Chizuk HM, Fong HF, Hannon M, Mannix RC. The Journal of the American Medical Association. 2026.
6. Mini Symptom Index Tool Plus Modified Vestibular-Ocular Motor Screening (mSIT Plus) for Acute Concussion Identification: Findings From the NCAA-DoD CARE Consortium. — Rooks LT, Pasquina PF, Broglio S, et al. British Journal of Sports Medicine. 2026.
7. Clinical Policy: Critical Issues in the Management of Adult Patients Presenting to the Emergency Department With Mild Traumatic Brain Injury: Approved by ACEP Board of Directors, February 1, 2023 Clinical Policy Endorsed by the Emergency Nurses Association (April 5, 2023). — Valente JH, Anderson JD, Paolo WF, et al. Annals of Emergency Medicine. 2023.
8. Diagnosis, Prognosis, and Clinical Management of Mild Traumatic Brain Injury. — Levin HS, Diaz-Arrastia RR. The Lancet. Neurology. 2015.
9. Action Collaborative on Traumatic Brain Injury Care: Adapted Clinical Practice Guideline. — Silverberg ND, Lee K, Mikolić A, et al. Annals of Family Medicine. 2025.
10. Emergency Department Risk Factors for Post-Concussion Syndrome After Mild Traumatic Brain Injury: A Systematic Review. — Lubbers VF, van den Hoven DJ, van der Naalt J, et al. Journal of Neurotrauma. 2024.
11. Best Practices In The Management Of Traumatic Brain Injury. — Geoffrey T. Manley MD PhD, Gregory W. Albert MD MPH FAANS FACS FAAP, Gretchen M. Brophy PharmD BCPS FCCP FCCM FNCS MCCM, et al American College of Surgeons (2024). 2024.
12. Sport-Related Concussion in Children and Adolescents. — Halstead ME, Walter KD, Moffatt K. Pediatrics. 2018.
13. ACR Appropriateness Criteria® Head Trauma: 2021 Update. — Expert Panel on Neurological Imaging, Shih RY, Burns J, et al. Journal of the American College of Radiology : JACR. 2021.
14. Post-Traumatic Headache Attributed to Traumatic Brain Injury: Classification, Clinical Characteristics, and Treatment. — Ashina H, Eigenbrodt AK, Seifert T, et al. The Lancet. Neurology. 2021.
15. Association of Pharmacological Interventions With Symptom Burden Reduction in Patients With Mild Traumatic Brain Injury: A Systematic Review. — Feinberg C, Carr C, Zemek R, et al. JAMA Neurology. 2021.
16. Evaluation of Posttraumatic Headache Phenotype and Recovery Time After Youth Concussion. — Kamins J, Richards R, Barney BJ, et al. JAMA Network Open. 2021.
17. The Role of Nutrition in Mild Traumatic Brain Injury Rehabilitation for Service Members and Veterans. — Monti K, Conkright MW, Eagle SR, Lawrence DW, Dretsch LM. NeuroRehabilitation. 2024.
18. Nutritional Supplement and Dietary Interventions as a Prophylaxis or Treatment of Sub-Concussive Repetitive Head Impact and Mild Traumatic Brain Injury: A Systematic Review. — Feinberg C, Dickerson Mayes K, Jarvis RC, Carr C, Mannix R. Journal of Neurotrauma. 2023.
19. American Medical Society for Sports Medicine Position Statement on Concussion in Sport. — Harmon KG, Clugston JR, Dec K, et al. Clinical Journal of Sport Medicine : Official Journal of the Canadian Academy of Sport Medicine. 2019.
20. Ω-3 Fatty Acid Supplementation as a Potential Therapeutic Aid for the Recovery From Mild Traumatic Brain Injury/Concussion. — Barrett EC, McBurney MI, Ciappio ED. Advances in Nutrition. 2014.
21. Management of Concussion and Persistent Post-Concussive Symptoms for Neurologists. — Leddy JJ, Haider MN, Noble JM, et al. Current Neurology and Neuroscience Reports. 2021.
22. QT Prolongation After Minor Head Trauma in a Pediatric Patient. — Mubayed L, Romme A, Nguyen HH. Pediatric Cardiology. 2020.
23. Sport-Related Concussion Induces Transient Cardiovascular Autonomic Dysfunction. — Dobson JL, Yarbrough MB, Perez J, Evans K, Buckley T. American Journal of Physiology. Regulatory, Integrative and Comparative Physiology. 2017.
24. Diagnosis of Sports-Related Concussion Using Symptom Report or Standardized Assessment of Concussion. — Harmon KG, Whelan BM, Aukerman DF, et al. JAMA Network Open. 2024.
25. Concussion in Sport: Recommendations From the 6th International Conference on Concussion in Sport. — Lau K. American Family Physician. 2024.
26. An Anatomical and Physiological Basis for the Cardiovascular Autonomic Nervous System Consequences of Sport-Related Brain Injury. — La Fountaine MF. International Journal of Psychophysiology : Official Journal of the International Organization of Psychophysiology. 2018.
27. The Heart-Brain-Metabolism Axis in Cardiovascular and Neurologic Disease. — Tardo DT, Cortes-Canteli M, Fuster V, Sachdev PS, Kovacic JC. Journal of the American College of Cardiology. 2025.
28. The Association of Early Electrocardiographic Abnormalities With Brain Injury Severity and Outcome in Severe Traumatic Brain Injury. — Lenstra JJ, Kuznecova-Keppel Hesselink L, la Bastide-van Gemert S, et al. Frontiers in Neurology. 2021.
29. A Systematic Review of Treatments of Post-Concussion Symptoms. — Heslot C, Azouvi P, Perdrieau V, et al. Journal of Clinical Medicine. 2022.
30. The Adolescent Athlete and the Team Physician: A Consensus Statement. 2025 Update. — Putukian M, Leclere LE, Herring SA, et al. Medicine and Science in Sports and Exercise. 2026.