Timothy M. Sowerby, MD
Gastroenterology Physician · Petaluma, CA
Timothy M. Sowerby, MD is a gastroenterology physician with a practice address in Petaluma, California, and NPI 1063475952, issued on Apr 11, 2006. Check the license (California A50116, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Timothy M. Sowerby
- Credential
- MD
- Primary taxonomy
- Gastroenterology Physician 207RG0100X
- License numbers
- A50116 CA
A050116 CA
Self-reported in NPPES; status is on the state search - Practice location
- 3900 Lakeville Hwy, Petaluma, CA 94954
- Phone
- (707) 765-3900
- Enumerated
- Apr 11, 2006
- Record last updated
- Jan 15, 2026
- Entity
- Type 1 · individual
8 nearest gastroenterology physician records → All 2,140 in California → Look up another NPI →
Also registered at 3900 Lakeville Hwy
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Caroline Barnhart, MDObstetrics & Gynecology Physician1437618774
- Alexis Becker, CNMMidwife1225112584
- Sharina Belani, MDInternal Medicine Physician1700958550
Verify Timothy M. Sowerby in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A50116Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
82% fewer Medicare Part D claims than the average gastroenterology physician in 2024
149 Medicare Part D claims for 73 beneficiaries, against an average of 811 among the 16,445 providers of this specialty who prescribed in Part D. Brand-name drugs were 25% of claims.
Most prescribed
- Pantoprazole Sodium43 claims
- Omeprazole17 claims
- Linzess12 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Timothy M. Sowerby among 2,140 gastroenterology physician records in California
Timothy M. Sowerby, MD is one of 2,140 gastroenterology physician records with a practice address in California. 83% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 7% of them.
- NPI issued2006 · 7% of these records are older, 48% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileNo · 72% of these records are
- Record last updated2026 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RG0100X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gastroenterology Physician providers in California
There are 2,140 gastroenterology physician records in California.
All 2,140 in California → Every provider in Petaluma → Gastroenterology Physician nationwide →
The 8 gastroenterology physician records with the nearest ZIP codes
- Stephen Denigris, MDPetaluma, CA 949541699888610
- Wendy Davis, M.D.Corte Madera, CA 949251336293653
- Jennifer Frankel, M.D.Corte Madera, CA 949251194941799
- Elijah VerheyenCorte Madera, CA 949251780047332
- John Bettinger, M.D.Greenbrae, CA 949041225037500
- David Bloom, MDGreenbrae, CA 949041619931011
- Christopher Hogan, M.D.Greenbrae, CA 949041376867010
- Danny Kao, MDGreenbrae, CA 949041396709796
Common questions
What is Timothy M. Sowerby, MD's NPI number?
Timothy M. Sowerby, MD's National Provider Identifier (NPI) is 1063475952, issued on Apr 11, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Timothy M. Sowerby, MD located?
The NPPES record lists a practice address at 3900 Lakeville Hwy, Petaluma, CA, 94954. Phone: (707) 765-3900. Providers update this record themselves, so call before visiting.
How can I verify Timothy M. Sowerby, MD's license?
NPPES lists California license number A50116, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Timothy M. Sowerby, MD prescribe under Medicare Part D?
In 2024, Timothy M. Sowerby, MD had 149 Medicare Part D claims for 73 beneficiaries; the average among gastroenterology physician prescribers was 811. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.