Internal Medicine, Nephrology · Huntsville, AL
NPI
1578631784
Since 2006
Specialty
Internal Medicine, Nephrology
Code 207RN0300X
Group practices
2
Medicare group memberships
Hospitals
5
Hospital affiliations
2780 Bob Wallace Avenue
Huntsville, AL, 35805
Phone (256) 533-4626
Groups this clinician bills Medicare through
Medicare paid, 2024
$268K
2,263 services
Medicare patients, 2024
520
Average age 74
Drug cost, 2024
$303K
1,373 prescriptions
Company payments, 2025
$1,370
From 15 companies
Procedures and visits billed to Original Medicare, 2024
In 2024, the most common Medicare service billed by John A Clark was code 99232 (hospital e&m - subsequent), 575 times for 152 patients. In total John A Clark billed 2,263 services in 45 codes, and Medicare paid $268K.
| Code |
|---|
Official US government data: the national provider registry and Medicare enrollment records, linked by NPI. Last update of this record: 2026-04-21.
| Setting |
|---|
| Services |
|---|
| Patients |
|---|
| Paid per service |
|---|
| Medicare paid |
|---|
| 99232 Hospital E&M - Subsequent | Facility | 575 | 152 | $57.27 | $33K |
| 99213 Office E&M - Established | Office | 270 | 204 | $48.23 | $13K |
| G2211 Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's | Office | 251 | 178 | $10.98 | $2,755 |
| 90935 Hemodialysis | Facility | 222 | 55 | $51.11 | $11K |
| 90966 ESRD Related Services (not dialysis) | Office | 140 | 21 | $213.42 | $30K |
| 99223 Hospital E&M - Initial | Facility | 99 | 91 | $122.70 | $12K |
| 90945 Peritoneal Dialysis | Facility | 85 | 17 | $60.50 | $5,143 |
| 36902 A-V Fistula PCI | Office | 63 | 49 | $801.87 | $51K |
| 99214 Office E&M - Established | Office | 57 | 44 | $57.60 | $3,283 |
| 99152 Anesthesia | Office | 52 | 40 | $34.82 | $1,810 |
| 81003 Clinical Chemistry | Office | 44 | 44 | $2.20 | $96.8 |
| 99205 Office E&M - New | Office | 38 | 38 | $138.69 | $5,270 |
| 36215 Angiography | Office | 36 | 25 | $350.26 | $13K |
| 75710 Angiography | Office | 25 | 19 | $55.54 | $1,389 |
| 99222 Hospital E&M - Initial | Facility | 24 | 23 | $90.90 | $2,182 |
By year: 2022 $284K for 2,048 services; 2023 $261K for 2,020 services; 2024 $268K for 2,263 services.
Lab tests billed to Medicare, 2024
| Test code | Tests | Patients | Paid per test | Medicare paid |
|---|---|---|---|---|
| 81003 Clinical Chemistry | 44 | 44 | $2.20 | $96.8 |
Medicare prescription drug claims, 2024
In 2024, the drug John A Clark prescribed most often to Medicare patients was Paricalcitol, with 144 prescriptions and refills. In total John A Clark wrote 1,373 Medicare prescriptions that cost $303K.
| Drug | Claims | 30-day fills | Patients | Cost |
|---|---|---|---|---|
| Paricalcitol Generic | 144 | 348 | 41 | $31K |
| Amlodipine Besylate Generic | 103 | 213 | 29 | $484 |
| Losartan Potassium Generic | 97 | 273 | 33 | $1,092 |
| Carvedilol Generic | 86 | 176 | 27 | $565 |
| Hydralazine Hcl Generic | 82 | 168 | 24 | $688 |
| Sevelamer Carbonate Generic | 77 | 119 | 27 | $11K |
| Furosemide Generic | 71 | 149 | 27 | $244 |
| Kerendia Finerenone | 58 | 74 | Under 11 | $46K |
| Allopurinol Generic | 56 | 108 | 11 | $285 |
| Calcitriol Generic | 46 | 132 | 20 | $1,098 |
| Nifedipine Er Nifedipine | 44 | 104 | 16 | $1,367 |
| Velphoro Sucroferric Oxyhydroxide | 39 | 43 | Under 11 | $80K |
| Lokelma Sodium Zirconium Cyclosilicate | 28 | 34 | Under 11 | $26K |
| Potassium Chloride Generic | 24 | 48 | 11 | $698 |
| Rayaldee Calcifediol | 22 | 26 | Under 11 | $38K |
Brand drugs: 207 claims; generic drugs: 1,166 claims.
Money and other things of value reported by the companies
In 2025, drug and medical device companies paid John A Clark $1,370 ($1,370 in general payments such as food, travel and fees) from 15 companies. The largest payer was Novartis Pharmaceuticals Corporation with $400.
| Company | Payments | Amount |
|---|---|---|
| Novartis Pharmaceuticals Corporation NVS | 15 | $400 |
| Travere Therapeutics, Inc. TVTX | 6 | $144 |
| Vifor Pharma, Inc. | 5 | $124 |
| Otsuka America Pharmaceutical, Inc. 4578.T | 6 | $121 |
| Boehringer Ingelheim Pharmaceuticals, Inc. | 5 | $92.34 |
| Amgen Inc. AMGN | 5 | $84.52 |
| Novo Nordisk Inc NVO | 4 | $82.08 |
| Ardelyx, Inc. ARDX | 3 | $67.51 |
| AstraZeneca Pharmaceuticals LP AZN | 4 | $63.03 |
| OPKO Pharmaceuticals, LLC | 4 | $62.74 |
Official US government data on Original Medicare services, Medicare prescription drug plans and the payments drug and device companies must report. Services with fewer than 11 patients and drugs with fewer than 11 claims are not published. Procedure codes are shown by number with their public category.