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Glasgow Coma Scale (GCS)

The Glasgow Coma Scale sums eye opening (1–4), verbal response (1–5) and motor response (1–6) for a total of 3–15. Head injury severity: 13–15 mild, 9–12 moderate, ≤8 severe (consider airway protection).

  • Eye opening: Spontaneous (4) (4); To sound / voice (3) (3); To pressure / pain (2) (2); None (1) (1)
  • Verbal response: Oriented (5) (5); Confused (4) (4); Inappropriate words (3) (3); Incomprehensible sounds (2) (2); None (1) (1)
  • Motor response: Obeys commands (6) (6); Localizes to pain (5) (5); Normal flexion / withdraws (4) (4); Abnormal flexion / decorticate (3) (3); Extension / decerebrate (2) (2); None (1) (1)
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Interpretation

ResultMeaning
13–15Mild brain injury
9–12Moderate
3–8Severe; "8, intubate" rule of thumb

Formula

GCS = Eye (1–4) + Verbal (1–5) + Motor (1–6); range 3–15

Clinical pearls

  • Report components (e.g. E3V4M6), not just the total; the motor score carries most prognostic weight.
  • In intubated patients the verbal score cannot be assessed: record as "VT" (e.g. E2VTM4) rather than assigning 1.
  • Confounded by sedation, intoxication, aphasia and paralysis.

Examples

gcs e3 v4 m6glasgow coma scale: eyes open to pain, incomprehensible sounds, withdraws from painGCS E1 V1 M2

FAQ

What GCS is considered severe?

A GCS of 8 or less indicates severe brain injury / coma.

What is the lowest possible GCS?

3 (E1 V1 M1); a GCS can never be 0.

Evidence

  1. Teasdale G, Jennett B. Assessment of coma and impaired consciousness: a practical scale. Lancet 1974;2:81–4.

Pulmonary & Critical Care · Reviewed 2026-10-14 · Methodology