Kevin Sieja, M.D.
Gastroenterology (CMS) · Denver, CO
At a glance
4500 E 9Th Ave Ste 720S, Denver, CO 80220-3926
Published activity: Colonoscopy · Upper gastrointestinal (GI) endoscopy for acid reflux. View counts and coverage
NPPES record updated Jun 30, 2026. Public records can lag behind changes at a practice.
Before you call: a quick checklist
- Are you accepting new patients?
- Do you accept my specific insurance plan?
- Do you provide the service I need at this address?
- Do I need a referral, and what is the earliest appointment?
Insurance participation and appointment availability are not established by these public records.
Medicare & insurance
Insurance participation is not established by these public records. Ask the practice and your insurer about your specific plan and this location.
How to check your coverage
Use your plan’s provider directory or the member-services number on your insurance card. Confirm the clinician, practice address, service, and whether a referral is required. A missing opt-out record does not establish Medicare acceptance.
Check the official Medicare directory ↗Practice location
4500 E 9Th Ave Ste 720SDenver, CO 80220-3926
Additional reported practice locations
50 Buck Creek Rd Ste 200Avon, CO 816205428
Phone: 9709266340 180 S Frontage Rd W Ste 5800
Vail, CO 816575038
Phone: 9709266340
Education & affiliations
- Medical / professional school
- Not reported in this file
- Graduation year
- 2000
- CMS specialties
- Gastroenterology
Practice groups
- Colorado Gastroenterology Prof Llc
- Colorado Mountain Medical, Llc
- Denver Digestive Health Specialists Inc
Reported hospital affiliations
- Hca Healthone Rose Denver, CO
- Hca Healthone Presbyterian St. Lukes Denver, CO
- Valley View Hospital Association Glenwood Springs, CO
Graduation year does not establish years in practice. A reported affiliation does not establish employment, current admitting privileges, or insurance participation.
Source: CMS National Downloadable File · Published Oct 15, 2026.
Source: CMS Facility Affiliation Data · Published Oct 15, 2026.
Procedures in the public data
Reported activity can help you ask more informed questions about a practice’s services.
| Procedure category | Published Medicare activity |
|---|---|
| Colonoscopy | 75 |
| Upper gastrointestinal (GI) endoscopy for acid reflux | 46 |
CMS uses a one-year claims window with a reporting lag. Counts cover the Medicare activity included by CMS, not all patients. “1–10” is a published range. Volume is not a quality or outcomes score. Coverage and methodology
Source: CMS Utilization Data · Published Oct 15, 2026.
Find providers with a similar service mix
Compare 2024 published Medicare activity in the same reported specialty, here or in another city.
Industry-reported general payments
Includes reported transfers of value, such as meals, travel, or consulting. Payments do not establish improper conduct or quality of care. Research funding and ownership values are excluded from this total.
See payment purposes and reporting companies
Reported purposes
| Purpose | Amount |
|---|---|
| Food and beverage | $1,357.39 |
Reporting companies
| Company | Amount |
|---|---|
| ABBVIE INC. | $245.72 |
| TAKEDA PHARMACEUTICALS U.S.A., INC. | $188.15 |
| LILLY USA, LLC | $152.92 |
| GILEAD SCIENCES, INC. | $113.37 |
| REGENERON HEALTHCARE SOLUTIONS, INC. | $101.17 |
| GENZYME CORPORATION | $100.07 |
| IPSEN BIOPHARMACEUTICALS, INC | $95.54 |
| JANSSEN BIOTECH, INC. | $72.23 |
| Other reporting companies | $288.22 |
Source: CMS 2025 payments grouped by covered recipient and nature of payments · Published Jun 30, 2026.
Professional details: NPI, taxonomy & registry record
Registry details
- Primary taxonomy
- Gastroenterology (CMS)
- Taxonomy code
- 207RG0100X
- Enumeration date
- May 23, 2006
- Record updated
- Jun 30, 2026
More registry details
- Provider type
- Individual · Type 1
- Reported credentials
- M.D.
Reported taxonomies and licenses
207RG0100X · Primary
License reported: 44150 CO
License numbers and credentials are reported to NPPES; HCPList does not independently verify them.
Practice location
4500 E 9Th Ave Ste 720SDenver, CO 80220-3926
- Phone
- (303) 355-3525
- Fax
- (303) 355-0255
Mailing address
4500 E 9TH AVE STE 720SDENVER, CO 802203926
Information may be outdated or incomplete. Confirm details directly with the practice. HCPList is an independent directory and is not affiliated with CMS.
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