Doctor profile · Federal record
Dr. Warren Chang, MD
Nephrology Physician (CMS: Nephrology) · Daly City, CA
- NPI 1083674550
- Accepts Medicare
- 28 yrs in practice
- Male
- Solo practice
- No sanctions
Practice & contact
- Primary practice
-
1498 Southgate Ave, Suite 102
Daly City, CA 940154015
(650) 755-4492
fax (650) 755-4466 - Mailing address
-
2149 E Warner RD Ste 102
Tempe, AZ 852843495
Credentials & registration
- NPI registered
- March 2006 — 20 yrs on file
- Profile last updated
- August 26, 2019
- Year of graduation
- 1998 — 28 yrs since
- Specialty taxonomy
- 207RN0300X — NUCC code
- State license (1)
- California #AG9500
- Medicaid
- CA #00A695000
Federal sanctions & exclusions
No sanctions, exclusions or revocations on file
Checked against OIG LEIE on NPI 1083674550. Last verified May 11, 2026.Medicare procedures · 2023
Top services delivered
Total services
1,370
Distinct HCPCS
10
Medicare allowed
$237,224
| HCPCS | Description | Services | Patients | Avg allowed | |
|---|---|---|---|---|---|
99214 |
Established patient office or other outpatient visit, 30-39 minutes | 327 | 143 | $113 | |
99232 |
Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes | 211 | 108 | $90 | |
99233 |
Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes | 210 | 104 | $132 | |
90960 |
Dialysis services, 4 or more physician visits per month (20 years or older) | 169 | 35 | $406 | |
99215 |
Established patient office or other outpatient visit, 40-54 minutes | 122 | 56 | $142 | |
99291 |
Critical care, first 30-74 minutes | 122 | 45 | $237 | |
99223 |
Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes | 76 | 72 | $194 | |
90935 |
Hemodialysis procedure with physician evaluation | 74 | 47 | $80 | |
90961 |
Dialysis services, 2-3 physician visits per month (20 years or older) | 36 | 15 | $339 | |
99205 |
New patient office or other outpatient visit, 60-74 minutes | 23 | 23 | $260 |
In context: peer comparison
Among 4 peers in this city , average services per provider: 118. This provider delivers 12× the peer median.Open Payments
Industry payments received
All-time total
$1,421
Transactions
55
Manufacturers
15
| Payer (manufacturer) | Industry | Txns | Amount |
|---|---|---|---|
| AstraZeneca Pharmaceuticals LP | 11 | $258.31 | |
| Mallinckrodt Hospital Products Inc. | 6 | $168.69 | |
| Novartis Pharmaceuticals Corporation | 4 | $123.71 | |
| CALLIDITAS THERAPEUTICS US INC. | 5 | $107.14 | |
| Amgen Inc. | 5 | $103.78 | |
| Novo Nordisk Inc | 5 | $100.59 | |
| Otsuka America Pharmaceutical, Inc. | 3 | $75.49 | |
| Fresenius USA Marketing, Inc. | 3 | $68.31 | |
| Vifor Pharma, Inc. | 2 | $65.20 | |
| OPKO Pharmaceuticals, LLC | 3 | $58.62 | |
| Otsuka Pharmaceutical Development & Commercialization, Inc. | 2 | $56.00 | |
| Aurinia Pharma U.S., Inc. | 2 | $52.53 | |
| Lilly USA, LLC | 2 | $49.21 | |
| Travere Therapeutics, Inc. | 1 | $35.21 | |
| Takeda Pharmaceuticals U.S.A., Inc. | 1 | $27.62 |
By nature of payment
Medicare Part D · 2023
Top prescriptions
Total claims
1,235
Patients
325
Total drug cost
$242,301
| Drug | Type | Claims | Patients | Total cost |
|---|---|---|---|---|
| Farxiga (Dapagliflozin Propanediol) | Brand | 180 | 36 | $164,002 |
| Prosol (Parenteral Amino Acid 20% No.1) | Brand | 153 | 0 | $19,824 |
| Amlodipine Besylate | Generic | 144 | 43 | $2,141 |
| Hydralazine Hcl | Generic | 135 | 47 | $3,483 |
| Calcitriol | Generic | 92 | 29 | $2,643 |
| Chlorthalidone | Generic | 81 | 23 | $1,896 |
| Losartan Potassium | Generic | 74 | 24 | $1,563 |
| Irbesartan | Generic | 68 | 18 | $2,876 |
| Furosemide | Generic | 65 | 24 | $691 |
| Labetalol Hcl | Generic | 51 | 19 | $2,819 |
Hospital affiliations
Frequently asked questions
What is Dr. Warren Chang's medical specialty?
Dr. Warren Chang practices Nephrology Physician in Daly City, CA.
Where does Dr. Warren Chang practice?
Dr. Warren Chang practices at 1498 Southgate Ave, Daly City, CA 940154015. Office phone: 6507554492.
What is Dr. Warren Chang's NPI?
Dr. Warren Chang's National Provider Identifier (NPI) is 1083674550, issued by NPPES.
Does Dr. Warren Chang accept Medicare assignment?
Yes. Dr. Warren Chang accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Warren Chang commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99214); Subsequent hospital care with moderate levelof medical decision making (HCPCS 99232); Subsequent hospital care with moderate levelof medical decision making (HCPCS 99233). Source: CMS Medicare Physician & Other Practitioners file.