Glasgow Coma Scale for nurses: how to score the GCS step by step

Quick answer: The Glasgow Coma Scale (GCS) rates level of consciousness on three components: eye opening (E) 1–4, verbal response (V) 1–5 and motor response (M) 1–6. The total runs from 3 to 15. Always document the components, not just the sum: for example E3V4M6 = 13. A component you cannot assess (such as verbal response in an intubated patient) is not scored; it is recorded as "NT" (not testable) with the reason.

Graham Teasdale and Bryan Jennett described the GCS in 1974 to give clinicians a shared language for consciousness after acute brain injury. Today it is one of the core tools of neurological monitoring in the emergency department, ICU and on the floor, and it shows up in skills check-offs, clinicals and NCLEX-style questions. This guide covers the scoring table, the structured approach recommended by the team behind the scale, and worked examples.

GCS scoring table

Older textbooks may say "opens eyes to pain" or "withdraws from pain." The current official version of the scale describes the stimulus as pressure and uses the terms in the table above.

How to tell the responses apart

Eye opening

• Spontaneous: eyes are already open before you approach.
• To sound: opens eyes to speech or a loud voice.
• To pressure: opens eyes only when you apply fingertip pressure.
• None: no eye opening to any stimulus, with no interfering factor.

Verbal response

• Oriented: correctly gives name, place and month/year.
• Confused: speaks in sentences but is disoriented.
• Words: intelligible single words.
• Sounds: only moans or groans.
• None: no verbal response.

Motor response

• Obeys commands: follows a two-part request such as "squeeze my hand, then let go."
• Localizing: brings a hand above the clavicle toward a stimulus on the head or neck.
• Normal flexion: the arm bends quickly at the elbow but does not localize.
• Abnormal flexion: slow, stereotyped flexion of the arm.
• Extension: the arm straightens at the elbow.
• None: no motor response.

Score the best motor response. If the right and left sides differ, use the better side for the score and document the difference separately: asymmetry is an important finding on its own.

The official structured approach: Check, Observe, Stimulate, Rate

The official Glasgow Coma Scale website recommends four steps to improve accuracy and agreement between assessors:

1. Check for factors that interfere with assessment: intubation, periorbital swelling, hearing loss, language barrier, sedation, spinal cord injury.
2. Observe what the patient does spontaneously before you give any stimulus: are the eyes open, are they talking, are they moving their arms?
3. Stimulate if there is no spontaneous response: first sound (normal voice, then a louder voice), then physical stimulus. The updated guidance describes fingertip pressure, trapezius pinch and supraorbital notch pressure.
4. Rate the response you observed against the defined criteria and record the best response.

Total score and severity

The total ranges from 3 (no response) to 15 (full response). A commonly used classification in traumatic brain injury is:

• 13–15: mild
• 9–12: moderate
• 3–8: severe

Clinical references often cite GCS ≤8 as a warning sign for the airway. The decision to intubate is not made from that number alone; it depends on whether the patient can protect their airway, their oxygenation and the overall clinical picture, and it is a team and provider decision.

Important: the total is convenient but loses information. The same total can describe very different patients, which is why the developers of the scale recommend reporting each component.

Worked examples

Example 1. As you approach, the patient's eyes are closed; they open when you say the patient's name. The patient talks but doesn't know the month and doesn't think they are in a hospital. They follow "squeeze my hand, let go." → E3 (to sound), V4 (confused), M6 (obeys commands) = E3V4M6, GCS 13

Example 2. No response to voice. Fingertip pressure makes the patient open their eyes and moan; with trapezius pressure their hand comes up to the neck. → E2 (to pressure), V2 (sounds), M5 (localizing) = E2V2M5, GCS 9

Example 3. Intubated patient. Opens eyes spontaneously and follows commands. → E4, V NT (intubated), M6. Because verbal response can't be assessed, document the components and the reason instead of a total: E4 V(NT) M6.

GCS-P: adding pupil reactivity

The GCS-Pupils (GCS-P) score, described in 2018, adds pupil reactivity as a marker of brainstem function. Calculation: GCS total − pupil reactivity score. The pupil reactivity score is 0 if both pupils react to light, 1 if one does not, and 2 if neither does, so GCS-P ranges from 1 to 15. For a nursing student the key point is that pupil assessment complements the GCS; it doesn't replace it.

Nursing tips

• The trend matters more than a single score. The real strength of the GCS is showing change in the same patient over time. Record every assessment with the time and the components.
• Report a decline promptly. Deterioration in even one component is a finding to escalate according to your facility's protocol.
• Use the same method. Assessing the patient together at shift change reduces differences between assessors. Giving the GCS inside an SBAR report keeps the handoff clear.
• Document interfering factors. Sedation, alcohol, hypoglycemia, intubation or periorbital edema can change the score; write down why.
• Children are different. Verbal responses in young children are judged by age; use a pediatric version of the GCS.

Common mistakes

1. Recording only the total and not the components.
2. Going straight to a physical stimulus without trying sound first.
3. Scoring the worse side for the motor response.
4. Giving an intubated patient V1 (correct: NT).
5. Confusing localizing with normal flexion: when localizing, the hand goes to the site of the stimulus.

For a quick review, use the Glasgow Coma Scale glossary entry, and connect neuro checks to the wider assessment with the ABCDE approach and vital signs entries.

Practice with Finito Nursing

Reading the GCS table once is not enough; the hard calls (localizing or normal flexion?) need repetition. Finito Nursing turns your lecture slides into flashcards and quizzes, uses spaced repetition to bring each card back just before you'd forget it, and gives you step-by-step clinical cases to practice neurological assessment. Start free in your browser.

FAQ

What is the lowest and highest Glasgow Coma Scale score?

The lowest is 3 and the highest is 15. Each component starts at 1, so the total can never be zero.

What does a GCS of 15 mean?

The patient opens their eyes spontaneously, is oriented and obeys commands. That corresponds to a normal level of consciousness, but it does not rule out other neurological findings.

How do you document GCS for an intubated patient?

Verbal response can't be assessed and is recorded as "NT" (not testable). Score eyes and motor, and document the components and the reason for NT instead of a total.

What is the difference between localizing and normal flexion?

When localizing, the patient brings a hand to the site of the stimulus on the head or neck. In normal flexion the arm bends quickly at the elbow, but the hand doesn't move toward the stimulus.

How often should GCS be checked?

The patient's condition, the provider's order and your facility's protocol set the frequency. Patients at risk of deterioration are assessed more often.

Sources

• Teasdale G, Jennett B. Assessment of coma and impaired consciousness: a practical scale. Lancet. 1974;2(7872):81–84.
• Teasdale G, Maas A, Lecky F, Manley G, Stocchetti N, Murray G. The Glasgow Coma Scale at 40 years: standing the test of time. Lancet Neurology. 2014;13(8):844–854.
• Brennan PM, Murray GD, Teasdale GM. Simplifying the use of prognostic information in traumatic brain injury. Part 1: The GCS-Pupils score. Journal of Neurosurgery. 2018;128(6):1612–1620.
• Glasgow Coma Scale official website: the structured approach
• Jain S, Iverson LM. Glasgow Coma Scale. StatPearls. Treasure Island (FL): StatPearls Publishing.