Mark Willoughby, M.D.
NPI 1215931993 · Dermatology Physician · Chula Vista, CA
Enrolled with Medicare as Practitioner - Dermatology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Willoughby, M.D. is a Dermatology Physician provider in Chula Vista, CA (NPI 1215931993).
Provider details
- NPI number
- 1215931993
- Entity type
- Individual
- Primary specialty
- Dermatology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- License
- A69750 (CA)
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
21 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
5,624 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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 1,451 | $97 |
| Destruction of Precancer Skin Growth, 2-14 Growths17003 | 1,164 | $8 |
| Pathology Examination of Tissue Using a Microscope, Intermediate Complexity88305 | 759 | $38 |
| Biopsy of Related Skin Growth, First Growth11102 | 495 | $112 |
| Destruction of Precancer Skin Growth, 1 Growth17000 | 440 | $73 |
| New Patient Office Or Other Outpatient Visit With Low Level of Medical Decision Making, If Using Time, 30 Minutes Or More99203 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 17 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Fluocinonide | 210 | 113 |
| Hydrocortisone | 117 | 91 |
| Clobetasol Propionate | 110 | 69 |
| Triamcinolone Acetonide | 106 | 76 |
| Ketoconazole | 64 | 35 |
| Fluorouracil | 39 | 34 |
| Doxycycline Hyclate | 34 | 16 |
| Minocycline Hcl | 34 | 17 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$1,226 across 60 records (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
Registry dates
- Enumerated
- 2005-06-09
- Last updated
- 2007-07-08
Frequently asked questions
- What is Mark Willoughby's NPI number?
- Mark Willoughby's National Provider Identifier (NPI) is 1215931993, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Willoughby's specialty?
- Mark Willoughby is listed in the NPPES registry with a primary specialty of Dermatology Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Willoughby located?
- Mark Willoughby's practice location on file with NPPES is 319 F St, Chula Vista, CA 91910-2666.
- What is Mark Willoughby's phone number?
- The practice phone number listed in the NPPES registry for Mark Willoughby is (619) 476-1200.
- Does Mark Willoughby accept Medicare?
- Mark Willoughby is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Willoughby's NPI active?
- Yes — Mark Willoughby's NPI (1215931993) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.