Glasgow Coma Scale
Level of consciousness
- Glasgow, 1974
- NICE NG232 head injury
Sources last checked: 2026-10-13
Glasgow Coma Scale
Level of consciousness
Record the three components separately too — the total score hides which domain is impaired.
Interpretation
| 3–8 — severe | Coma range. NICE NG232 recommends early advanced airway management by a trained clinician at GCS ≤ 8. |
|---|---|
| 9–12 — moderate | Moderate class in the conventional head-injury severity grading. |
| 13–15 — mild | Mild class in the conventional head-injury severity grading; a GCS below 15 still indicates impaired consciousness. |
What is the Glasgow Coma Scale?
The Glasgow Coma Scale describes the level of consciousness from three components: eye opening (1–4), verbal response (1–5) and best motor response (1–6). Teasdale and Jennett introduced it in Glasgow in 1974; the total ranges from 3 to 15. It is used worldwide in trauma, neurology, intensive care and pre-hospital medicine.
When to use it
- Initial and serial assessment after head injury and in any patient with reduced consciousness.
- Monitoring for neurological deterioration (a fall of 2 points, or 1 point in the motor score, is significant).
- Communicating conscious level between teams and in triage, using the components as well as the total.
When not to use it
- Sedated, paralysed or intubated patients — record the component as 'not testable' (NT) rather than 1.
- Young children — use the paediatric GCS adapted for pre-verbal patients.
- As a stand-alone predictor of outcome in an individual patient.
How it is calculated
| Criterion | Points |
|---|---|
| Eye opening | |
| Spontaneous | 4 |
| To sound | 3 |
| To pressure | 2 |
| None | 1 |
| Verbal response | |
| Oriented | 5 |
| Confused | 4 |
| Words | 3 |
| Sounds | 2 |
| None | 1 |
| Best motor response | |
| Obeys commands | 6 |
| Localises | 5 |
| Normal flexion | 4 |
| Abnormal flexion | 3 |
| Extension | 2 |
| None | 1 |
Clinical pearls and limitations
- Record the three components separately too — the total score hides which domain is impaired.
- Always report the components, e.g. E2 V3 M5 = 10; the same total can describe very different patients.
- Use a standardised peripheral (nail-bed) and central (trapezius or supraorbital) pressure stimulus.
- The motor response is the strongest prognostic component.
- Current terminology (Teasdale 2014): 'to sound' and 'to pressure' replace 'to speech' and 'to pain'.
- GCS ≤ 8 is the conventional threshold for severe brain injury; NICE NG232 links it to early advanced airway management.
Frequently asked questions
At what GCS do you intubate?
A GCS of 8 or less is the widely used trigger for securing the airway after head injury; NICE NG232 recommends early advanced airway management by a trained clinician at this level. Other factors (loss of airway reflexes, hypoxaemia, deterioration) also matter.
What are mild, moderate and severe head injury on the GCS?
By convention: 13–15 mild, 9–12 moderate, 3–8 severe. These categories describe groups; individual decisions also depend on the component scores and imaging.
How do I score GCS in an intubated patient?
The verbal component cannot be tested; record it as 'NT' or 'T' (e.g. E3 VT M5) rather than scoring 1, and report the components instead of a misleading total.
Evidence and guidelines
- Primary source: Teasdale G, Jennett B. Assessment of coma and impaired consciousness. A practical scale. Lancet 1974;304(7872):81-84.
- Teasdale G et al. The Glasgow Coma Scale at 40 years: standing the test of time. Lancet Neurol 2014;13(8):844-854 (current terminology; report components separately).
- NICE guideline NG232. Head injury: assessment and early management (2023) — GCS 8 or less: early advanced airway management.
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