Mark Cahill, MD
NPI 1598957888 · Gastroenterology Physician · Tualatin, OR
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Cahill, MD is a Gastroenterology Physician provider in Tualatin, OR (NPI 1598957888).
Provider details
- NPI number
- 1598957888
- Entity type
- Individual
- Primary specialty
- Gastroenterology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- MD29414 (OR)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
18 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
261 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
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 .
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) |
|---|---|---|
| Pathology Examination of Tissue Using a Microscope, Intermediate Complexity88305 | 72 | $40 |
| Removal of Polyps Or Growths of Large Bowel Using an Endoscope With Mechanical Snare45385 | 58 | $245 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 32 | $130 |
| Biopsy of Esophagus, Stomach, And/Or Upper Small Bowel Using a Flexible Endoscope43239 | 23 | $83 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 20 | $93 |
| Biopsy of Large Bowel Using a Flexible Endoscope |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 12 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Omeprazole | 121 | 59 |
| Pantoprazole Sodium | 47 | 22 |
| Ondansetronbrand: Ondansetron Odt | 42 | 38 |
| Ondansetron Hcl | 37 | 37 |
| Lansoprazole | 30 | — |
| Carvedilol | 24 | — |
| Peg3350/Sod Sulf,bicarb,cl/Kclbrand: Peg-3350 and Electrolytes | 22 | 21 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$32 across 1 record (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 1508 Division St Ste 10Oregon City, OR 97045-1582Phone: (503) 692-3750Fax: (503) 691-2324
Registry dates
- Enumerated
- 2007-08-10
- Last updated
- 2023-11-28
- Certified
- 2023-11-28
Frequently asked questions
- What is Mark Cahill's NPI number?
- Mark Cahill's National Provider Identifier (NPI) is 1598957888, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Cahill's specialty?
- Mark Cahill is listed in the NPPES registry with a primary specialty of Gastroenterology Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Cahill located?
- Mark Cahill's practice location on file with NPPES is 19250 Sw 90th Ave, Tualatin, OR 97062-7585.
- What is Mark Cahill's phone number?
- The practice phone number listed in the NPPES registry for Mark Cahill is (503) 692-3750.
- Does Mark Cahill accept Medicare?
- Mark Cahill is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Cahill's NPI active?
- Yes — Mark Cahill's NPI (1598957888) is active in the NPPES registry as of the last update on 2023-11-28.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.