Neuroleptic Malignant Syndrome Diagnostic Criteria

Scores the international consensus diagnostic criteria for neuroleptic malignant syndrome over eight weighted findings.

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Dopamine antagonist exposure
Yes
Hyperthermia above 100.4 F on at least two occasions, measured orally
Yes
Rigidity
Yes
Mental status alteration
Yes
Creatine kinase at least four times the upper limit of normal
Yes
Negative work-up for infectious, toxic, metabolic and neurologic causes
Yes

Result: a priority total of 85 of 100, at or above the threshold of 74

The tool opens with these values already filled in. Replace them with your own.

What the result means

The points
Exposure or dopamine agonist withdrawal 20, hyperthermia 18, rigidity 17, mental status alteration 13, creatine kinase 10, sympathetic lability 10, negative work-up 7, hypermetabolism 5.
74 or more of 100
Supports the diagnosis. A total below it does not exclude the syndrome; a patient may be treated on suspicion regardless.
Not a severity scale
The points weigh how much each finding argues for the diagnosis. A higher total does not mean a sicker patient and does not grade anything.
Fever and rigidity
Neither is required. The threshold is reachable without hyperthermia, which leaves 82 points, and without rigidity, which leaves 83.
The negative work-up
A scored item worth 7 points, not a precondition. It adds to the total without gating it, and the diagnosis remains one of exclusion in practice.
Creatine kinase
At least four times the upper limit of normal. Any lesser elevation does not score the item.

What you enter

  • Dopamine antagonist exposure, or dopamine agonist withdrawal, within the past 72 hours (20 points)
  • Hyperthermia above 100.4 F on at least two occasions, measured orally (18 points)
  • Rigidity (17 points)
  • Mental status alteration: reduced or fluctuating level of consciousness (13 points)
  • Creatine kinase at least four times the upper limit of normal (10 points)
  • Sympathetic nervous system lability: at least two of a blood pressure rise of 25 percent or more above baseline, a swing of 20 mmHg diastolic or 25 mmHg systolic within 24 hours, diaphoresis, or urinary incontinence (10 points)
  • Negative work-up for infectious, toxic, metabolic and neurologic causes (7 points)
  • Hypermetabolism: a heart rate 25 percent or more above baseline together with a respiratory rate 50 percent or more above baseline (5 points)
How this is calculated

Gurrera RJ, Caroff SN, Cohen A, et al. An international consensus study of neuroleptic malignant syndrome diagnostic criteria using the Delphi method. J Clin Psychiatry. 2011;72(9):1222-1228. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.