Sternbach Criteria (Serotonin Syndrome)
The Sternbach criteria for serotonin syndrome (Sternbach 1991).
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Mental status changes
- Yes
- Agitation
- Yes
- Myoclonus
- No
- Hyperreflexia
- Yes
- Diaphoresis
- No
- Shivering
- No
- Tremor
- No
- Diarrhea
- No
- Incoordination
- No
- Fever
- No
The other 4 values
- Rigidity
- No
- The features coincided with the ADDITION of
- Yes
- Other causes have been RULED OUT
- Yes
- A neuroleptic had NOT been started or increased in dosage before onset
- Yes
Result: Meets
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What the result means
- Features
- Mental status changes, agitation, myoclonus, hyperreflexia, diaphoresis, shivering, tremor, diarrhea, incoordination, fever.
- Requirement 1
- The features coincided with the ADDITION or INCREASE of a known serotonergic agent.
- Requirement 2
- Other causes RULED OUT: infectious, metabolic or endocrine, substance abuse or withdrawal.
- Requirement 3
- A HARD NEGATIVE - a neuroleptic had NOT been started or increased. NMS is the differential.
- Non-specific
- A patient on an SSRI with a febrile gastroenteritis can reach 3 of 10 without serotonin toxicity.
- Disputed item
- One review adds RIGIDITY as an eleventh feature. Not counted here; flagged when counting it would flip the verdict.
- Successor
- CONTESTED. Hunter 84/97% vs Sternbach 75/96%, but the Hunter derivation and validation data overlapped. "Obsolete" is not settled.
- Scope
- FAILING THESE DOES NOT EXCLUDE serotonin syndrome. Does not grade severity or select treatment.
What you enter
- Mental status changes (confusion, hypomania).
- Agitation.
- Myoclonus.
- Hyperreflexia.
- Diaphoresis.
- Shivering.
- Tremor.
- Diarrhea.
- Incoordination.
- Fever.
The other 4 fields
- Mental status changes (confusion, hypomania). One of the 10 features; 3 are required and are not sufficient on their own.
- Agitation. One of the 10 features; 3 are required and are not sufficient on their own.
- Myoclonus. One of the 10 features; 3 are required and are not sufficient on their own.
- Hyperreflexia. One of the 10 features; 3 are required and are not sufficient on their own.
- Diaphoresis. One of the 10 features; 3 are required and are not sufficient on their own.
- Shivering. One of the 10 features; 3 are required and are not sufficient on their own.
- Tremor. One of the 10 features; 3 are required and are not sufficient on their own.
- Diarrhea. One of the 10 features; 3 are required and are not sufficient on their own.
- Incoordination. One of the 10 features; 3 are required and are not sufficient on their own.
- Fever. One of the 10 features; 3 are required and are not sufficient on their own.
- Rigidity. THE DISPUTED ELEVENTH FEATURE: present in one authoritative reproduction and not in the widely used ten-item list. It is NOT counted here, but it sets `verdictDependsOnDisputedFeature` when counting it would change the answer.
- The features coincided with the ADDITION of, or an INCREASE in, a known serotonergic agent. A REQUIREMENT, NOT A SYMPTOM: "no" defeats the diagnosis however many features are present.
- Other causes have been RULED OUT - infectious, metabolic or endocrine, substance abuse or withdrawal. A REQUIREMENT, NOT A SYMPTOM: "no" defeats the diagnosis however many features are present.
- A neuroleptic had NOT been started or increased in dosage before onset. A REQUIREMENT, NOT A SYMPTOM: "no" defeats the diagnosis however many features are present.
How this is calculated
- Rule
- At least 3 of 10 features PLUS all three requirements. 3 of 10 is NECESSARY AND NOT SUFFICIENT.
Sternbach H. The serotonin syndrome. Am J Psychiatry. 1991;148(6):705-713. Compared figures from Dunkley EJC, Isbister GK, Sibbritt D, et al. The Hunter Serotonin Toxicity Criteria. QJM. 2003;96(9):635-642. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.