ICD 10 Coding Alert

Question: Encounter notes indicate that the provider performed a level-three office evaluation and management (E/M) service for an established patient. Final diagnosis was “Parkinson, w/o dyskinesia, w/fluctuations, w/o OFF episodes.” What is the correct ICD-10-CM code for this condition, and what is an OFF episode?

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Answer: As of Oct. 1, the correct code for this condition is G20.A1 (Parkinson’s disease without dyskinesia, without mention of fluctuations). One of the alternate terms for G20.A1 is “Parkinson’s disease without dyskinesia, without mention of OFF episodes.” Use this diagnosis on your claim.

More on OFF episodes: When a patient has Parkinson’s, they will have periods where their medication is working effectively; this is called an ON period. Once the medication starts being less effective for the patient’s symptoms, it is called an OFF period.

There were also several more additions to the G20.- (Parkinson’s disease) ICD-10-CM code set. Here are the codes that were effective Oct.1, along with the alternate terms for each diagnosis:

• G20.A1
  o Parkinson’s disease NOS
  o Parkinson’s disease without dyskinesia, without mention of OFF episodes
• G20.A2 (Parkinson’s disease without dyskinesia, with fluctuations)
  ​o Parkinson’s disease without dyskinesia, with OFF episodes
• G20.B1 (Parkinson’s disease with dyskinesia, without mention of fluctuations)
  o Parkinson’s disease with dyskinesia, without mention of OFF episodes

• G20.B2 (Parkinson’s disease with dyskinesia, with fluctuations)
  o Parkinson’s disease with dyskinesia, with OFF episodes

• G20.C (Parkinsonism, unspecified)
  o Parkinsonism, NOS.