Serotonin syndrome
- G90.81 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
- ICD-10-CM G90.81 is a new 2025 ICD-10-CM code that became effective on October 1, 2024.
- This is the American ICD-10-CM version of G90.81 – other international versions of ICD-10 G90.81 may differ.
Applicable To
- Serotonin toxicity
Use Additional
- 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 First
- 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)
The following code(s) above G90.81 contain annotation back-references
that may be applicable to G90.81:
- G00-G99 Diseases of the nervous system
- G90 Disorders of autonomic nervous system
ICD-10-CM G90.81 is grouped within Diagnostic Related Group(s) (MS-DRG v42.0):
- 073 Cranial and peripheral nerve disorders with mcc
- 074 Cranial and peripheral nerve disorders without mcc
Code History
- 2025 (effective 10/1/2024): New code
Diagnosis Index entries containing back-references to G90.81: