ICD-10-CM 2027
ICD-10 code for olfactory hallucination
From the official ICD-10-CM alphabetic index entry “Hallucination › olfactory”. Page updated September 29, 2026.
About coding olfactory hallucination
The ICD-10-CM code for olfactory hallucination is R44.2 (Other hallucinations).
Within R44, choose R44.2 (Other hallucinations) only when documentation doesn't support a more specific option: auditory hallucinations (R44.0), visual hallucinations (R44.1), hallucinations, unspecified (R44.3), other symptoms and signs involving general sensations and perceptions (R44.8) and unspecified symptoms and signs involving general sensations and perceptions (R44.9).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 880 (Acute Adjustment Reaction and Psychosocial Dysfunction, relative weight 0.9306), in MDC 19 (Mental Diseases and Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about olfactory hallucination ICD-10 codes
What is the ICD-10 code for olfactory hallucination?
- R44.2 — Other hallucinations.
Is R44.2 billable?
- Yes. R44.2 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can R44.2 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict R44.2 as a principal diagnosis.
Is R44.2 a CC or MCC?
- R44.2 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.