What is Douglas Flagg's NPI number?

Douglas Flagg's National Provider Identifier (NPI) is 1821178013, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.

What is Douglas Flagg's specialty?

Douglas Flagg is listed in the NPPES registry with a primary specialty of Rheumatology Physician (Allopathic & Osteopathic Physicians).

Where is Douglas Flagg located?

Douglas Flagg's practice location on file with NPPES is 1611 S Green Rd # 65, South Euclid, OH 44121-4129.

What is Douglas Flagg's phone number?

The practice phone number listed in the NPPES registry for Douglas Flagg is (216) 291-4050.

Does Douglas Flagg accept Medicare?

Douglas Flagg is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.

Is Douglas Flagg's NPI active?

Yes — Douglas Flagg's NPI (1821178013) is active in the NPPES registry as of the last update on 2010-11-16.

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Douglas Flagg, MD

NPI 1821178013 · Rheumatology Physician · South Euclid, OH

Douglas Flagg, MD is a Rheumatology Physician provider in South Euclid, OH (NPI 1821178013).

Provider details

NPI number: 1821178013
Entity type: Individual
Primary specialty: Rheumatology PhysicianAllopathic & Osteopathic Physicians
Credential: MD
Sex: Male
Sole proprietor: No
License: 35-056239 (OH)

Practice location

1611 S Green Rd # 65

South Euclid, OH 44121-4129

Phone: (216) 291-4050

Fax: (216) 691-3524

Street-level locationGet directions

More OH providers

Mailing address

Po Box 8792

Belfast, ME 04915-8792

Specialties & taxonomies

Rheumatology PhysicianPrimary207RR0500XLicense 35-056239 (OH)
Allopathic & Osteopathic Physicians

Enrolled with Medicare as Order and Referring Only - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)

Profile Score

Detailed profile(91/100 index)

A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.

Registry tenure38% of score
20 yrs in NPPES registry
Profile completeness38% of score
100% of core fields populated
Practice footprint23% of score
1 documented practice location

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.

Enumerated: 2006-10-16
Last updated: 2010-11-16

Frequently asked questions

What is Douglas Flagg's NPI number?: Douglas Flagg's National Provider Identifier (NPI) is 1821178013, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
What is Douglas Flagg's specialty?: Douglas Flagg is listed in the NPPES registry with a primary specialty of Rheumatology Physician (Allopathic & Osteopathic Physicians).
Where is Douglas Flagg located?: Douglas Flagg's practice location on file with NPPES is 1611 S Green Rd # 65, South Euclid, OH 44121-4129.
What is Douglas Flagg's phone number?: The practice phone number listed in the NPPES registry for Douglas Flagg is (216) 291-4050.
Does Douglas Flagg accept Medicare?: Douglas Flagg is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
Is Douglas Flagg's NPI active?: Yes — Douglas Flagg's NPI (1821178013) is active in the NPPES registry as of the last update on 2010-11-16.

Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.

Provider details

Practice location

Mailing address

Specialties & taxonomies

Profile Score

Registry dates

Frequently asked questions

Specialties & taxonomies

Profile Score

Frequently asked questions