Physician Profile
Stephen Yoon, M.D.
Unclaimed ProfileAbout Dr. Yoon
Based in Fullerton, CA, Stephen Yoon, M.D. is listed in the NPI registry under internal medicine. Stephen graduated from Rutgers New Jersey Medical School in 1998. According to Medicare claims data, Stephen cared for 460 Medicare patients across 663 services. The services billed most often include subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes, subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes, and hospital discharge day management, more than 30 minutes.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it.
Education & Training
Specialty
Credentials & Licensing
License numbers are what the provider reported to NPPES when the NPI was issued or updated. NPPES does not verify licensure; confirm current standing with the state licensing board.
Contact Information
- (714) 992-3000
- Email not available
Practice Locations
101 E VALENCIA MESA DR
Fullerton, CA 92835
Conditions Commonly Evaluated or Treated
Within Internal Medicine generally. Availability varies by clinician, training and location — this profile has not been claimed, so nothing here is a personal claim by the provider.
Conditions
Most searched conditions
- Allergies
- Diabetes
- Flu
- Hypothyroidism
- Strep throat
- UTI
Cardiometabolic
- High blood pressure
- High cholesterol
Digestive and liver
- Acid reflux
- Fatty liver disease
- IBS
Endocrine, blood, and bone
- Gout
Infectious disease
- Shingles
Kidney and urinary
- Chronic kidney disease
- Enlarged prostate
Respiratory
- Acute bronchitis
- Asthma
- COPD
Blood & Circulation
- Blood clots
Blood disorders
- Anemia
Brain & Nerves
- Alzheimer's disease
Brain and nerves
- Vertigo
Cardiac and vascular
- AFib
Digestive
- Diverticulitis
Heart & Circulation
- Heart disease
Infections
- Impetigo
Kidney & Bladder
- Overactive Bladder and Leakage
Lungs & Breathing
- Sleep apnea
Mental Health
- Generalized anxiety disorder
- Insomnia and Sleep Problems
Neurologic and behavioral
- Depression
- Migraines
Pain
- Back pain
Rheumatologic and pain
- Osteoarthritis
Procedures & services
Most searched procedures
- Annual physical
- Blood test
- Flu shot
- Medicare wellness visit
- Sick visit
- TB test
- Well-woman exam
Preventive and evaluation
- Medication management
- Post-hospital transitional care
Screening and diagnostic testing
- EKG
- Spirometry
Bones & Joints
- Trigger Point Injections
Brain and nerves
- Epley Maneuver
Cancer screening
- Colon Cancer Screening Referral
- Mammogram Referral
Digestive
- Endoscopy
Exams & Consultations
- Pre-Op Clearance Exam
Heart & Circulation
- Blood Pressure Check
- Heart monitor
Heart health
- Cardiac Stress Test Referral
Imaging referral
- Abdominal Ultrasound Referral
Immunizations
- Tetanus shot
Lab tests
- Urinalysis
Lungs & Breathing
- At-Home Sleep Study Order
Metabolic & Weight
- Weight Loss Injections and Medication
Minor procedures
- Ingrown toenail removal
- Suture removal
Office procedures
- Cryotherapy for skin lesions
- Earwax removal
- Incision and drainage of an abscess
- Skin biopsy
Office Procedures
- Skin Tag and Mole Removal
- Vitamin B12 Injections
- Wart Removal
Pain management
- Knee Joint Injection
Preventive & Routine Care
- Smoking cessation counseling
Screenings & Diagnostics
- Bone Density Scan Referral
- Diabetes Screening and A1C Test
Sexual health
- STI Testing
Procedures Most Often Billed to Medicare
663 services · 460 patients · 6 distinct codes
| Procedure | Type | Code | Services |
|---|---|---|---|
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes | Office visit | 99233 |
228 |
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes | Office visit | 99232 |
222 |
| Hospital discharge day management, more than 30 minutes | Office visit | 99239 |
114 |
| Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes | Office visit | 99222 |
50 |
| Hospital discharge day management, 30 minutes or less | Office visit | 99238 |
30 |
| Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes | Office visit | 99231 |
19 |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other internists at this location 6
Same specialty, same street address — most likely the same department or group.
Related specialists at this location 8
Clinically related specialties at the same address — the people this provider most likely works alongside.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
More connections — 22 related providers in 3 groups
Other internists in Fullerton 6
Same specialty, same city.
Trained at Rutgers New Jersey Medical School 8
Other providers in the same specialty who trained at the same institution.
Class of 1998 at Rutgers New Jersey Medical School 8
Providers who graduated from the same medical school in the same year.
Common questions
What does Stephen Yoon specialize in?
Stephen Yoon is an internist in Fullerton, CA. That is the designation recorded for this NPI in the federal registry, where it is listed as “Internal Medicine”.
NPI registry
Where is Stephen Yoon located?
Stephen Yoon is listed at 101 E Valencia Mesa Dr, Fullerton, CA 92835. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
What is Stephen Yoon's phone number?
The number on file is (714) 992-3000. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is Stephen Yoon's NPI number?
Stephen Yoon's National Provider Identifier is 1851327100. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Stephen Yoon train?
Stephen Yoon attended Rutgers New Jersey Medical School, graduating in 1998. This comes from the CMS National Downloadable File.
CMS public data
How long has Stephen Yoon been practicing?
Stephen Yoon has 28 years experience. Calculated from a graduation year of 1998, reported in the CMS National Downloadable File.
CMS public data
What does Stephen Yoon do most often?
According to Medicare billing data, Stephen Yoon the Medicare record under this individual NPI shows mainly office visits and diagnostic testing. Hospital-based physicians usually have their procedural work billed by the facility rather than under their own number, so this is a floor on their practice, not a description of it. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Has Stephen Yoon confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Stephen Yoon. If this is you, claiming it is free.
Guide.md
Provider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.