Dr. Daniel O. Claassen, M.D.
Neurology (Neurology Physician)
- Medicare participating
At a glance
- Medical school
- Medical College of Georgia School of Medicine (2005)
- Years since graduation
- 21
- In the NPI registry since
- 2006
- Medicare patients seen, 2024
- 52
The NPI date is when this clinician registered for a National Provider Identifier, the billing number used on health claims. It is not a license, graduation or board-certification date. NPIs were first issued in May 2005 and became required on claims in 2007–2008, so an early date usually means the clinician was already in practice before then. What an NPI is
Education and training
- 2005Medical school: Medical College of Georgia School of Medicine
- 2006Registered with an NPI (national billing number; not a license date) — NPIs began in 2005, so practice likely started earlier
Undergraduate school, residency, fellowship, licensing exams and board certification aren’t in public federal data. Board certification can be confirmed with the certifying board (ABMS member boards for MDs, AOA boards for DOs).
Specialties and state licenses
-
Neurology Physician primary
TN license 47418 -
Behavioral Neurology & Neuropsychiatry Physician
TN license 47418
As reported to the NPI registry. To confirm a license is current, check the state medical board.
Where they work
Hospitals
- Vanderbilt University Medical Center Nashville, TN
Medical groups
- Vanderbilt University Medical Center (3,567 clinicians)
Hospitals this clinician lists with Medicare, and groups they bill Medicare through (Care Compare). Affiliation doesn’t mean they see patients at every location.
Medicare patients and services
- Medicare patients, 2024
- 52
- Services billed
- 62
- Patients’ average age
- 73
| Service | Times | Patients |
|---|---|---|
| Established patient office or other outpatient visit, 40-54 minutes | 64 | 46 |
| New patient office or other outpatient visit, 60-74 minutes | 14 | 14 |
Medicare fee-for-service only. CMS leaves out services billed for fewer than 11 patients. These figures describe a practice’s Medicare work; they aren’t a measure of quality.
Medicare prescriptions
| Drug | Prescriptions |
|---|---|
| Austedo Xr (deutetrabenazine) Other prescribers in Nashville, TN | 30 |
| Austedo (deutetrabenazine) Other prescribers in Nashville, TN | 19 |
Prescriptions filled under Medicare Part D, including refills. CMS leaves out drugs prescribed fewer than 11 times.
Payments from drug and device companies
In 2025, 5 companies reported 36 payments worth $41,719 in total to this clinician.
| AbbVie Inc. | $16,268 |
|---|---|
| Neurocrine Biosciences, Inc. | $12,156 |
| Novartis Pharmaceuticals Corporation | $7,791 |
| Teva Pharmaceuticals USA, Inc. | $5,314 |
| Ptc Therapeutics, Inc. | $190 |
| Consulting Fee | $30,475 |
|---|---|
| Travel and Lodging | $10,054 |
| Food and Beverage | $1,190 |
What the payments were for
| Company | What it was for | Amount |
|---|---|---|
| Novartis Pharmaceuticals Corporation Jun 10, 2025 | Travel and Lodging travel to London, Great Britain (UK) · in-kind | $7,173 |
| AbbVie Inc. Mar 28, 2025 | Consulting Fee | $5,600 |
| AbbVie Inc. Mar 7, 2025 | Consulting Fee | $5,520 |
| Teva Pharmaceuticals USA, Inc. Feb 25, 2025 | Consulting Fee | $4,200 |
| Neurocrine Biosciences, Inc. Jan 29, 2025 | Consulting Fee | $4,000 |
| Neurocrine Biosciences, Inc. Feb 5, 2025 | Consulting Fee | $4,000 |
| Neurocrine Biosciences, Inc. May 27, 2025 | Consulting Fee | $4,000 |
| AbbVie Inc. Mar 28, 2025 | Consulting Fee | $1,440 |
| Teva Pharmaceuticals USA, Inc. Oct 27, 2025 | Consulting Fee | $915 |
| AbbVie Inc. Mar 7, 2025 | Travel and Lodging travel to BOSTON, MA · in-kind | $844 |
All 18 payments other than meals, newest first
| Company | What it was for | Amount |
|---|---|---|
| Teva Pharmaceuticals USA, Inc. Oct 27, 2025 | Consulting Fee | $915 |
| Novartis Pharmaceuticals Corporation Jun 10, 2025 | Travel and Lodging travel to London, Great Britain (UK) · in-kind | $7,173 |
| Novartis Pharmaceuticals Corporation Jun 10, 2025 | Travel and Lodging travel to London, Great Britain (UK) · in-kind | $357 |
| Neurocrine Biosciences, Inc. May 27, 2025 | Consulting Fee | $4,000 |
| AbbVie Inc. Mar 28, 2025 | Consulting Fee | $5,600 |
| AbbVie Inc. Mar 28, 2025 | Consulting Fee | $1,440 |
| AbbVie Inc. Mar 28, 2025 | Travel and Lodging travel to NASHVILLE, TN · in-kind | $60.00 |
| AbbVie Inc. Mar 28, 2025 | Travel and Lodging travel to NASHVILLE, TN · in-kind | $59.27 |
| AbbVie Inc. Mar 7, 2025 | Consulting Fee | $5,520 |
| AbbVie Inc. Mar 7, 2025 | Travel and Lodging travel to BOSTON, MA · in-kind | $844 |
| AbbVie Inc. Mar 7, 2025 | Travel and Lodging travel to CHICAGO, IL · in-kind | $661 |
| AbbVie Inc. Mar 7, 2025 | Travel and Lodging travel to BOSTON, MA · in-kind | $551 |
| AbbVie Inc. Mar 7, 2025 | Travel and Lodging travel to BOSTON, MA · in-kind | $167 |
| AbbVie Inc. Mar 6, 2025 | Travel and Lodging travel to CHICAGO, IL · in-kind | $181 |
| Teva Pharmaceuticals USA, Inc. Feb 25, 2025 | Consulting Fee | $4,200 |
| Neurocrine Biosciences, Inc. Feb 5, 2025 | Consulting Fee | $4,000 |
| Neurocrine Biosciences, Inc. Jan 29, 2025 | Consulting Fee | $4,000 |
| AbbVie Inc. Jan 14, 2025 | Consulting Fee VYALEV · NEUROSCIENCE | $800 |
Each payment as the company reported it, with the products it named. Meals are counted in the totals above but not listed one by one.
From CMS Open Payments. A payment is not evidence of wrongdoing; many are for consulting, teaching or meals. Clinicians can review and dispute their records with CMS.
Industry-funded research
Named as a principal investigator on 2 industry-funded studies in 2025, from 2 companies. The companies reported $22,096 in research payments for these studies, mostly to the institutions running them.
- Study To Assess Adverse Events and Change in Disease Activity Of 24-hour Continuous Subcutaneous Infusion Of ABBV-951 In Adult Participants With Advanced Parkinson's Disease
AbbVie Inc. · Completed · NCT04750226 - A Study to Evaluate the Safety and Efficacy of PTC518 in Participants With Huntington's Disease (HD)
Ptc Therapeutics, Inc. · Completed · NCT05358717
From CMS Open Payments research payments, where companies name up to five principal investigators per payment. Research payments usually go to hospitals, universities and research sites, not to the investigator personally. A payment is not evidence of wrongdoing.