Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Johannes Karl Martensson, M.D.

Gastroenterology Physician in Inverness, FL · enumerated 2005.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1417954298

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Registry record

Entity type Individual (Type 1)

Name Johannes Karl Martensson

Credential M.D.

Sex Male

Practice address 3653 E Forest Dr, Inverness, FL, 34453

Phone (352) 344-8080

Fax (352) 344-0631

Enumeration date Jul 7, 2005

Last updated in NPPES Sep 5, 2007

Taxonomy & licenses

207RG0100X Gastroenterology Physician Allopathic & Osteopathic Physicians · License ME71187 (FL) Primary

MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier	Type	State	Issuer
203499	Other	FL	AVMED HEALTH PLANS
76981	Other	NY	VYTRA HEALTH PLANS
MD984FL	Other	AK	ALASKA MEDICAID
P2957611	Other	FL	OXFORD HEALTH PLANS
2158646	Other	CA	FIRST HEALTH
2900908	Other	FL	UNITED HEALTH CARE
32728	Other	FL	BCBS OF FLORIDA
6015923	Other	NY	GROUP HEALTH INCORPORATED
0250317	Other	FL	CIGNA HEALTHCARE

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

How do I verify Johannes Martensson's NPI record?

Cross-check NPI 1417954298 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

Is NPI 1417954298 active?

Yes, as of the latest NPPES snapshot, NPI 1417954298 is active (record last updated 2007-09-05).

Other providers at this practice address

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Citrus Gastroenterology PA Gastroenterology Physician · Inverness, FL NPI 1407853195 Citrus Gastroenterology Mgt Plc Gastroenterology Physician · Inverness, FL NPI 1043506611

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-09-05.