William Cain, MD
NPI 1821083973 · Allergy & Immunology Physician · Hermitage, TN
Enrolled with Medicare as Practitioner - Allergy/Immunology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Cain, MD is a Allergy & Immunology Physician provider in Hermitage, TN (NPI 1821083973).
Provider details
- NPI number
- 1821083973
- Entity type
- Individual
- Primary specialty
- Allergy & Immunology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- MD38400 (TN)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Other Service Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 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
23,421 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) |
|---|---|---|
| Professional Service for Preparation and Provision of 1 Or More Antigens95165 | 15,540 | $13 |
| Test for Allergy Using Allergenic Extract95004 | 3,795 | $3 |
| Professional Service for Multiple Injections of Allergen95117 | 2,839 | $11 |
| Test for Allergy Using Allergenic Extract Injected Into Skin95024 | 730 | $7 |
| Professional Service for Single Injection of Allergen95115 | 213 | $9 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 88 | $82 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 32 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Montelukast Sodium | 385 | 119 |
| Famotidine | 307 | 103 |
| Fluticasone Propionate | 291 | 132 |
| Azelastine Hcl | 166 | 73 |
| Omalizumabbrand: Xolair | 159 | 17 |
| Albuterol Sulfatebrand: Albuterol Sulfate Hfa | 135 | 81 |
| Triamcinolone Acetonide | 78 | 57 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$1,474 across 69 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
- 2005-09-14
- Last updated
- 2016-03-10
Frequently asked questions
- What is William Cain's NPI number?
- William Cain's National Provider Identifier (NPI) is 1821083973, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Cain's specialty?
- William Cain is listed in the NPPES registry with a primary specialty of Allergy & Immunology Physician (Allopathic & Osteopathic Physicians).
- Where is William Cain located?
- William Cain's practice location on file with NPPES is 5045 Old Hickory Blvd, Hermitage, TN 37076-2582.
- What is William Cain's phone number?
- The practice phone number listed in the NPPES registry for William Cain is (615) 475-0148.
- Does William Cain accept Medicare?
- William Cain is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Cain's NPI active?
- Yes — William Cain's NPI (1821083973) is active in the NPPES registry as of the last update on 2016-03-10.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.