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2 Minute MedicineICD-10 Lookup

ICD-10-CM code · FY2027

G90.81 Serotonin syndrome

BillableValid for claims as a specific diagnosis code

About G90.81

Code
G90.81
Billable
Yes
Short description
Serotonin syndrome
Category
G90 Disorders of autonomic nervous system
Block
G89-G99 Other disorders of the nervous system
Chapter
6 Diseases of the nervous system
Code set
FY2027, October 1, 2026 to September 30, 2027

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Coding notes for G90.81

Applicable to Other names for conditions reported with this code.

  • Serotonin toxicity

Code first Report the underlying condition's code before this one.

  • poisoning due to drug or toxin, such as:
  • linezolid (T36.8X- with sixth character 1-4)
  • monoamine oxidase inhibitors (T43.1X with sixth character 1-4)
  • selective serotonin and norepinephrine reuptake inhibitors [SSNRI] (T43.21 with sixth character 1-4)
  • selective serotonin reuptake inhibitors [SSRI] (T43.22 with sixth character 1-4)

Use additional code Add a second code for the detail named here.

  • code for adverse effect, if applicable, to identify drug, such as:
  • linezolid (T36.8X5)
  • monoamine oxidase inhibitors (T43.1X5)
  • selective serotonin and norepinephrine reuptake inhibitors [SSNRI] (T43.215)
  • selective serotonin reuptake inhibitors [SSRI] (T43.225)
  • code, if applicable, to identify:
  • disseminated intravascular coagulation (D65)
  • hypertensive crisis (I16.-)
  • metabolic acidosis (E87.2-)
  • shock, not elsewhere classified (R57.-)
  • toxic encephalopathy (G92.-)
  • ventricular tachycardia (I47.2-)

Also applies, from G90 Disorders of autonomic nervous system

Excludes1 Not coded here: never report these together with this code (use the code given instead).

  • dysfunction of the autonomic nervous system due to alcohol (G31.2)
Chapter 6 notes (apply to every code in it)

Excludes2 Not part of this condition, but a patient can have both: report both codes when both apply.

  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Related codes in G90.8

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