Welby Nielsen, D.O.
Child & Adolescent Psychiatry Physician · San Luis Obispo, CA
Welby Nielsen, D.O. is a child & adolescent psychiatry physician with a practice address in San Luis Obispo, California, and NPI 1962611947, issued on May 22, 2007. Check the license (California 20A11177, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Welby Nielsen
- Credential
- D.O.
- Primary taxonomy
- Child & Adolescent Psychiatry Physician 2084P0804X
- License number
- 20A11177 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1039 Murray Ave Ste 220, San Luis Obispo, CA 93405
- Phone
- (805) 250-2996
- Enumerated
- May 22, 2007
- Record last updated
- Mar 29, 2018 (not updated in 8 years: call before relying on the address or phone)
- Fax
- (805) 250-2998
- Medicare enrollment
- Enrolled (PECOS I20110713000806); accepts Medicare assignment
- Medical or professional school
- University Of Arizona College Of Medicine, 2005
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest child & adolescent psychiatry physician records → All 1,009 in California → Look up another NPI →
Also registered at 1039 Murray Ave Ste 220
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Peter Afsari, D.O.Psychiatry Physician1013126143
- Amanda SelmanPsychiatric/Mental Health Nurse Practitioner1326602913
- Kristin Toney, APRN- NPPsychiatric/Mental Health Nurse Practitioner1952853624
- Elizabeth ZarekMarriage & Family Therapist1942913785
Verify Welby Nielsen in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A11177Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
71% fewer Medicare Part D claims than the average child & adolescent psychiatry physician in 2024
147 Medicare Part D claims for 14 beneficiaries, against an average of 504 among the 3,545 providers of this specialty who prescribed in Part D. Brand-name drugs were 12% of claims.
Most prescribed
- Escitalopram Oxalate28 claims
- Gabapentin25 claims
- Aripiprazole13 claims
- Trintellix13 claims
- Lisdexamfetamine Dimesylate12 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.
Bills Medicare through one group practice
- Mark David Levine MD Professional CorporationSan Luis Obispo, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Welby Nielsen among 1,009 child & adolescent psychiatry physician records in California
Welby Nielsen, D.O. is one of 1,009 child & adolescent psychiatry physician records with a practice address in California. 55% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2007, is newer than 35% of them.
- NPI issued2007 · 35% of these records are older, 41% newer
- In a Medicare fileYes · 55% of these records are
- In the CMS Doctors and Clinicians fileYes · 21% of these records are
- Graduated2005 · median 2005 among the 215 with a school on file
- Record last updated2018 · 57% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 2084P0804X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Child & Adolescent Psychiatry Physician providers in California
There are 1,009 child & adolescent psychiatry physician records in California.
All 1,009 in California → Every provider in San Luis Obispo → Child & Adolescent Psychiatry Physician nationwide →
The 8 child & adolescent psychiatry physician records with the nearest ZIP codes
- Deborah Brewster, MDSan Luis Obispo, CA 934011356518088
- Douglas Murphy, MDSan Luis Obispo, CA 934011700953734
- Daniel Olivieri, M.D.San Luis Obispo, CA 934011104023662
- Todd Elwyn, M.D.Atascadero, CA 934221700035367
- Heather Barrett, M.D.Lompoc, CA 934361487712311
- Angeline De Guzman, M.D.Santa Maria, CA 934541437224896
- Marsha Guerra, MDBakersfield, CA 933091316365828
- Frederic Rowe, M.D.Bakersfield, CA 933091871634014
Common questions
What is Welby Nielsen, D.O.'s NPI number?
Welby Nielsen, D.O.'s National Provider Identifier (NPI) is 1962611947, issued on May 22, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Welby Nielsen, D.O. located?
The NPPES record lists a practice address at 1039 Murray Ave Ste 220, San Luis Obispo, CA, 93405. Phone: (805) 250-2996. Providers update this record themselves, so call before visiting.
How can I verify Welby Nielsen, D.O.'s license?
NPPES lists California license number 20A11177, 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 Welby Nielsen, D.O. prescribe under Medicare Part D?
In 2024, Welby Nielsen, D.O. had 147 Medicare Part D claims for 14 beneficiaries; the average among child & adolescent psychiatry physician prescribers was 504. 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.