Quick answers
- Does Adam C. Zweig accept Medicare assignment?
- Yes. Medicare's clinician data says Adam C. Zweig accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Adam C. Zweig see?
- In 2024, CMS data shows 88 Original Medicare patients and 717 services for Adam C. Zweig. This counts Original Medicare only and measures volume, not quality.
- What is Adam C. Zweig's NPI number?
- 1265527600. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Adam C. Zweig, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 88 |
|---|---|
| Services billed to Medicare | 717 |
| Different services or procedures | 20 |
| Participating Medicare provider | Yes |
| Average age of these patients | 65 |
Most frequent services
- Insertion of needle into vein for collection of blood sample (36415)231 services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)219 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)47 services
- Injection of drug or substance under skin or into muscle (96372)44 services
- Admn sarscov2 vacc 1 dose (90480)34 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High cholesterol55%
- High blood pressure51%
- Arthritis32%
- Depression31%
- Anxiety25%
- Diabetes23%
Practice locations
Addresses where Adam C. Zweig is enrolled with Medicare (CMS data updated October 2, 2026).
- 400 30th StOakland, CA 94609 (510) 628‑2949
- 518 A Castro StSan Francisco, CA 94114 (415) 552‑2814
Group practices
Medicare enrollment lists Adam C. Zweig as a member of this group (CMS data updated October 2, 2026).
- Aids Healthcare Foundation101 clinicians in the group
Specialties
- Internal Medicineprimary
Other internal medicine doctors in Oakland
Clinicians with the same Medicare primary specialty in Oakland, CA — not a recommendation.
Other clinicians in Aids Healthcare Foundation
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of California, San Diego School Of Medicine |
| Graduation year | 1989 (37 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1265527600 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians