Gregory Hahn, DO
NPI 1972702215 · Psychiatry Physician · Merriam, KS
Enrolled with Medicare as Practitioner - Psychiatry · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Gregory Hahn, DO is a Psychiatry Physician provider in Merriam, KS (NPI 1972702215).
Provider details
- NPI number
- 1972702215
- Entity type
- Individual
- Primary specialty
- Psychiatry PhysicianAllopathic & Osteopathic Physicians
- Credential
- DO
- Sex
- Male
- Sole proprietor
- No
- License
- 05-39922 (KS)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
18 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
867 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 264 | $116 |
| Visit Complexity Inherent to Evaluation and Management Associated With Medical Care Services That Serve As the Continuing Focal Point for All Needed Health Care Services And/Or With Medical Care Services That Are Part of Ongoing Care Related to a Patient'SG2211 | 259 | $15 |
| Hospital Discharge Day Management, More Than 30 Minutes99239 | 70 | $105 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 66 | $110 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 61 | $167 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 57 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Clonazepam | 326 | 74 |
| Trazodone Hcl | 271 | 77 |
| Quetiapine Fumarate | 244 | 46 |
| Duloxetine Hcl | 184 | 48 |
| Bupropion Hclbrand: Bupropion Xl | 146 | 35 |
| Mirtazapine | 143 | 39 |
| Alprazolam |
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-07-17
- Last updated
- 2025-09-05
- Certified
- 2025-09-05
Frequently asked questions
- What is Gregory Hahn's NPI number?
- Gregory Hahn's National Provider Identifier (NPI) is 1972702215, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gregory Hahn's specialty?
- Gregory Hahn is listed in the NPPES registry with a primary specialty of Psychiatry Physician (Allopathic & Osteopathic Physicians).
- Where is Gregory Hahn located?
- Gregory Hahn's practice location on file with NPPES is 9100 W 74th St, Merriam, KS 66204-4004.
- What is Gregory Hahn's phone number?
- The practice phone number listed in the NPPES registry for Gregory Hahn is (913) 663-2642.
- Does Gregory Hahn accept Medicare?
- Gregory Hahn is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Gregory Hahn's NPI active?
- Yes — Gregory Hahn's NPI (1972702215) is active in the NPPES registry as of the last update on 2025-09-05.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.