Simin Siddiq, M.D.
NPI 1255362422 · Internal Medicine Physician · Fremont, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Simin Siddiq, M.D. is a Internal Medicine Physician provider in Fremont, CA (NPI 1255362422).
Provider details
- NPI number
- 1255362422
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Female
- Sole proprietor
- No
- License
- A38666 (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
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
809 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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 271 | $149 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 212 | $103 |
| Insertion of Needle Into Vein for Collection of Blood Sample36415 | 43 | $9 |
| Blood Test, Comprehensive Group of Blood Chemicals80053 | 33 | $10 |
| Complete Blood Cell Count (red Cells, White Blood Cell, Platelets), Automated Test and Automated Differential White Blood Cell Count85025 | 32 | $8 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 35 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Amlodipine Besylate | 181 | 59 |
| Metformin Hcl | 128 | 38 |
| Simvastatin | 118 | 36 |
| Losartan Potassium | 109 | 32 |
| Levothyroxine Sodium | 102 | 31 |
| Atorvastatin Calcium | 81 | 27 |
| Alendronate Sodium | 75 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$62 across 3 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
- 2006-07-06
- Last updated
- 2010-04-15
Frequently asked questions
- What is Simin Siddiq's NPI number?
- Simin Siddiq's National Provider Identifier (NPI) is 1255362422, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Simin Siddiq's specialty?
- Simin Siddiq is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Simin Siddiq located?
- Simin Siddiq's practice location on file with NPPES is 2333 Mowry Ave, Fremont, CA 94538.
- What is Simin Siddiq's phone number?
- The practice phone number listed in the NPPES registry for Simin Siddiq is (510) 796-0222.
- Does Simin Siddiq accept Medicare?
- Simin Siddiq is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Simin Siddiq's NPI active?
- Yes — Simin Siddiq's NPI (1255362422) is active in the NPPES registry as of the last update on 2010-04-15.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.