Sam Ahn, M.D.
NPI 1558423814 · Allergy & Immunology (Internal Medicine) Physician · Napa, CA
Enrolled with Medicare as Practitioner - Allergy/Immunology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Sam Ahn, M.D. is a Allergy & Immunology (Internal Medicine) Physician provider in Napa, CA (NPI 1558423814).
Provider details
- NPI number
- 1558423814
- Entity type
- Individual
- Primary specialty
- Allergy & Immunology (Internal Medicine) PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 147289 (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
19 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
15,517 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) |
|---|---|---|
| Test for Allergy Using Allergenic Extract95004 | 9,216 | $4 |
| Professional Service for Multiple Injections of Allergen95117 | 1,492 | $14 |
| Test for Allergy Using Allergenic Extract Injected Into Skin95024 | 1,257 | $9 |
| Professional Service for Preparation and Provision of 1 Or More Antigens95165 | 1,223 | $16 |
| Injection of Drug Or Substance Under Skin Or Into Muscle96372 | 754 | $15 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 400 | $95 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 36 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Ipratropium Bromide | 256 | 114 |
| Montelukast Sodium | 204 | 58 |
| Azelastine Hcl | 163 | 70 |
| Albuterol Sulfatebrand: Albuterol Sulfate Hfa | 155 | 65 |
| Fluticasone/Umeclidin/Vilanterbrand: Trelegy Ellipta | 120 | 26 |
| Levocetirizine Dihydrochloride | 113 | 37 |
| Fluticasone Propionate | 81 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$3,424 across 78 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
Additional practice locations (1)
- 414 W Napa St Ste BSonoma, CA 95476-6519Phone: (707) 258-8100Fax: (707) 258-0734
Registry dates
- Enumerated
- 2006-12-14
- Last updated
- 2023-03-07
- Certified
- 2020-02-05
Frequently asked questions
- What is Sam Ahn's NPI number?
- Sam Ahn's National Provider Identifier (NPI) is 1558423814, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Sam Ahn's specialty?
- Sam Ahn is listed in the NPPES registry with a primary specialty of Allergy & Immunology (Internal Medicine) Physician (Allopathic & Osteopathic Physicians).
- Where is Sam Ahn located?
- Sam Ahn's practice location on file with NPPES is 1100 Pear Tree Ln, Napa, CA 94558-6446.
- What is Sam Ahn's phone number?
- The practice phone number listed in the NPPES registry for Sam Ahn is (707) 258-8100.
- Does Sam Ahn accept Medicare?
- Sam Ahn is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Sam Ahn's NPI active?
- Yes — Sam Ahn's NPI (1558423814) is active in the NPPES registry as of the last update on 2023-03-07.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.