DR. JUSTIN PENG MD
NPI 1538328141
Internal Medicine - Rheumatology in Washington, DC

Q: What is Justin Peng's NPI number?

The NPI number for Justin Peng is 1538328141. It was assigned to this individual provider in the NPPES registry on June 9, 2008.

Q: What is Justin Peng's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Rheumatology, with taxonomy code 207RR0500X.

Q: When was this NPI record last updated?

The NPPES record for Justin Peng was last updated on February 5, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since June 09, 2008PECOS EnrolledAccepts Medicare Assignment

77.12/100

CMS Quality Rating

2021 K ST NW, SUITE 300, WASHINGTON, DC 20006(301) 942-7600(202) 419-0418 Get Directions Write a Review

NPPES record last updated: February 5, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Feb 5, 2026, Dec 20, 2021, Jan 10, 2020 (3 updates tracked since 2020).

On this page

About Dr. Justin Peng Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. JUSTIN PENG MD (NPI 1538328141) is an individual rheumatology provider in Washington, District Of Columbia, licensed in District Of Columbia (MD037073) and active in the NPI registry since June 2008. He is enrolled in Medicare PECOS, is affiliated with Virginia Hospital Center, and maintains a secondary practice location in Fairfax.

NPPES Registry Identity

NPI1538328141

Entity TypeIndividualMale

Primary Taxonomy207RR0500X

Provider Legal NameDR. JUSTIN PENGCredential: MD

Location Address2021 K ST NW, SUITE 300Washington, DC 20006-1003

Mailing Address7361 Calhoun Pl Ste 600Rockville, MD 20855-2788 · (301) 942-7600 · Fax (301) 942-3521

Phone(301) 942-7600

Fax(202) 419-0418

Sole ProprietorNo

Medical School CMSBoston University School Of MedicineGraduated 2005

Enumeration DateJune 9, 2008

Last NPPES UpdateFebruary 5, 20263 updates tracked since enumeration

NPPES CertifiedFebruary 5, 2026

✔ NPI 1538328141 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · RheumatologyAllopathic & Osteopathic Physicians

Taxonomy Code207RR0500X

Licenses✔ Licensed in DC · MD037073✔ Licensed in VA · 0101242489✔ Licensed in MD · D0072143

Definition

An internist who treats diseases of joints, muscle, bones and tendons. This specialist diagnoses and treats arthritis, back pain, muscle strains, common athletic injuries and collagen diseases.

2021 K ST NW, Washington, DC 20006

Open in Google Maps ↗

Secondary Practice Location 1

Location 18270 Willow Oaks Corporate Dr Ste 150Fairfax, VA 22031-4530 · Phone (301) 942-7600 · Fax (703) 573-7767

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Justin Peng Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID7517026214

PECOS Enrollment IDI20081111000047, I20241211000378

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Justin Peng reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Arthritis And Rheumatism Associates PC

15 mi

Rheumatology

14995 SHADY GROVE RD STE 250
Rockville, MD 20850

Reassigned Medicare billing, District of Columbia and Maryland enrollments
41 clinicians in this Medicare group

NPI 1447259866 (301) 942-7600

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 52

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Injection, tocilizumab, 1 mg J3262

Tocilizumab is a medication administered via injection. It's used to treat certain conditions like rheumatoid arthritis by reducing inflammation in the body. It works by blocking a substance in the body that leads to inflammation.

18,440 services17 patients

Injection, denosumab, 1 mg J0897

Denosumab is a medication given via injection to strengthen your bones. It works by slowing down the cells that break down bone, improving bone density and reducing the risk of fractures. It's often used for osteoporosis treatment.

8,040 services110 patients

Injection, abatacept, 10 mg (code may be used for medicare when drug administered under the direct supervision of a physician, not for use when drug is self administered) J0129

Abatacept is a medication administered via injection under a doctor's supervision. It's used to treat conditions like rheumatoid arthritis by moderating the immune system. This code applies when the doctor administers the drug, not for self-administration.

3,025 services11 patients

Injection, infliximab, excludes biosimilar, 10 mg J1745

Infliximab is a medication given via injection to treat certain autoimmune conditions. It works by blocking the action of a substance in your body that causes inflammation. Each dose is based on your medical condition and response to treatment.

1,790 services15 patients

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214

This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.

713 services352 patients

Blood test, comprehensive group of blood chemicals 80053

A comprehensive group of blood chemicals test, also known as a comprehensive metabolic panel, is a blood test that measures your sugar level, electrolyte and fluid balance, kidney function, and liver function. This helps to check your body's overall health.

471 services286 patients

Insertion of needle into vein for collection of blood sample 36415

This procedure involves inserting a small needle into a vein, typically in your arm, to collect a blood sample. It's a quick and simple process to help diagnose or monitor health conditions. You may feel a small prick, but discomfort is minimal.

458 services287 patients

Measurement c-reactive protein for detection of infection or inflammation 86140

C-reactive protein (CRP) test is a blood test that checks for signs of inflammation or infection in the body. High levels of CRP often suggest that there's inflammation or a bacterial infection. This test helps in monitoring and managing conditions like arthritis and heart disease.

390 services201 patients

Complete blood cell count (red cells, white blood cell, platelets), automated test and automated differential white blood cell count 85025

A Complete Blood Cell Count is a common test that measures various components of the blood, including red cells (carry oxygen), white cells (fight infection), and platelets (help blood clot). An automated test ensures accuracy. The differential count provides detailed information about white cell types.

333 services217 patients

Red blood cell sedimentation rate, to detect inflammation, automated 85652

The Red Blood Cell Sedimentation Rate is a test that helps detect inflammation in the body. It's automated, meaning a machine does the work. This test measures how fast red blood cells settle at the bottom of a tube in an hour. A faster rate may indicate inflammation.

284 services158 patients

Administration of non-hormonal anti-neoplastic chemotherapy under skin or into muscle 96401

This procedure involves giving anti-cancer drugs, which don't contain hormones, into the muscle or under the skin. These drugs help to stop the growth of cancer cells. The process is usually quick and done by a healthcare professional.

186 services118 patients

Administration of chemotherapy into vein, 1 hour or less 96413

Chemotherapy is a treatment that uses drugs to destroy cancer cells. When administered into a vein, it's often through an IV. This procedure usually lasts 1 hour or less. You may feel a slight pinch as the needle is inserted, but it's generally painless.

170 services61 patients

Dxa bone density measurement of hip, pelvis, spine 77080

A DXA bone density measurement is a simple, quick, and non-invasive procedure that assesses the strength of your bones. This test uses X-rays to measure the amount of minerals, mainly calcium, in the hip, pelvis, and spine. It helps in early detection of osteoporosis or other bone diseases.

166 services166 patients

Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213

This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.

157 services137 patients

Measurement of antibody for assessment of autoimmune disorder, any method 86235

This procedure measures the level of specific antibodies in your body to assess if you have an autoimmune disorder. Antibodies are proteins your immune system produces. In autoimmune disorders, these antibodies mistakenly attack your own cells. This test helps identify such conditions.

142 services22 patients

Vitamin d-3 level 82306

A Vitamin D-3 level test measures the amount of Vitamin D-3, a crucial nutrient, in your body. This test helps identify if your levels are too low or too high. Low levels may lead to bone weakness, while high levels could harm your kidneys. It's a simple blood test.

128 services126 patients

Destruction of peripheral nerve or branch 64640

Destruction of a peripheral nerve or branch is a procedure to treat nerve-related pain. It involves using heat, cold, or chemicals to damage or destroy the nerve, thereby blocking pain signals to the brain. This can provide long-term pain relief.

108 services20 patients

Measurement of complement (immune system proteins), antigen, 86160

The measurement of complement (immune system proteins) and antigen is a blood test. It helps to assess how your immune system is functioning. Complement proteins play a role in your body's immune response, and antigens trigger this response. This test helps in diagnosing and monitoring certain diseases.

86 services27 patients

Uric acid level, blood 84550

A blood uric acid level test measures the amount of uric acid in your blood. Uric acid is a waste product that your body produces when it breaks down purines, substances found in your body and in certain foods. High levels may lead to gout or kidney stones.

78 services64 patients

Administration of chemotherapy into vein, each additional hour 96415

Chemotherapy is a treatment method that uses drugs to destroy cancer cells. The drugs are administered into a vein, usually in the arm. Each additional hour of chemotherapy allows for more of the medication to enter your bloodstream to fight against the cancer cells.

77 services22 patients

X-ray of hand, minimum of 3 views 73130

An X-ray of the hand, minimum of 3 views, is a non-invasive imaging test. It uses a small amount of radiation to produce images of the bones in your hand from different angles. This helps in diagnosing fractures, infections, arthritis, or other abnormalities. It's quick and painless.

74 services37 patients

Calcium level, total 82310

A total calcium level test measures the amount of calcium in your blood. Calcium is essential for body functions like bone formation, nerve signal transmission, and muscle contraction. Abnormal levels may indicate conditions like bone disease or kidney disorders.

74 services62 patients

X-ray of knee, 3 views 73562

An X-ray of the knee, 3 views, is a non-invasive imaging test. It uses a small amount of radiation to produce images of the knee from three different angles. This helps medical professionals to diagnose and monitor conditions like arthritis, fractures, or infections. The process is quick and painless.

64 services32 patients

Complete ultrasound scan of joint 76881

A complete ultrasound scan of a joint is a non-invasive procedure using sound waves to create images of your joint. It helps identify problems like inflammation, injury, or disease. It's painless, safe, and doesn't involve radiation.

63 services54 patients

Screening test for antibody to noninfectious agent 86255

A screening test for antibodies to noninfectious agents is a medical procedure that checks your body's response to substances that are not infectious. It involves taking a blood sample to identify specific antibodies, which are proteins your body produces when it detects harmful elements.

63 services27 patients

Injection, zoledronic acid, 1 mg J3489

Zoledronic acid is a medication given via injection to strengthen bones. It's often used in patients with osteoporosis or certain types of cancer. The injection helps reduce the risk of fractures and other bone complications.

60 services12 patients

Aspiration and/or injection of fluid large joint using ultrasound guidance 20611

This procedure involves using ultrasound technology to accurately locate a large joint, usually the knee or shoulder. A needle is then inserted to either extract fluid (aspiration) or inject medication. The ultrasound helps ensure precision and safety.

55 services28 patients

New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204

This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.

53 services53 patients

Injection of drug or substance under skin or into muscle 96372

This procedure involves administering medication directly under the skin or into a muscle. A small needle is used to inject the drug, allowing it to be absorbed quickly into the bloodstream. It's a common method for delivering a variety of medications.

52 services21 patients

Ultrasonic guidance for needle placement 76942

Ultrasonic guidance for needle placement is a technique where sound waves create images that help accurately position the needle during procedures. This method ensures precision, minimizes discomfort, and increases safety.

48 services37 patients

Rheumatoid factor level 86431

The Rheumatoid Factor Level test is a blood test that helps detect the presence of Rheumatoid Factor (RF), a protein produced by your immune system. High RF levels often indicate autoimmune diseases like rheumatoid arthritis. The test involves a simple blood draw and lab analysis.

44 services43 patients

Measurement of antibody for rheumatoid arthritis assessment 86200

This procedure measures the level of certain antibodies in your blood. These antibodies can be higher in people with rheumatoid arthritis, a condition causing joint inflammation. The test helps in diagnosing or monitoring the disease.

42 services41 patients

X-ray of foot, minimum of 3 views 73630

An X-ray of the foot, minimum of 3 views, is a non-invasive imaging test. It uses a small amount of radiation to produce images of the bones and tissues in your foot. This helps to identify fractures, infections, or other abnormalities. Multiple views ensure a comprehensive examination.

40 services20 patients

Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more 99215

This service involves a follow-up appointment for existing patients, lasting between 40 to 54 minutes. During this time, your healthcare provider will assess your current health status, discuss any changes or concerns, review your treatment plan, and answer any questions you may have.

33 services28 patients

Infusion into a vein for therapy, prevention, or diagnosis, 1 hour or less 96365

This is a procedure where a medical professional inserts a small tube into your vein to deliver medication, nutrients, or fluids directly into your bloodstream. This can be for treatment, prevention, or diagnosis. The process typically takes less than an hour.

32 services16 patients

Manual urinalysis test with examination using microscope, automated 81001

A manual urinalysis test with automated microscopic examination is a lab process that checks your urine for health indicators. It involves a machine scanning your sample to identify any abnormal elements, which can assist in diagnosing various conditions.

27 services16 patients

Creatinine level to test for kidney function or muscle injury 82570

A creatinine level test measures the amount of creatinine in your blood. This substance is a waste product from normal muscle use. Higher levels can indicate possible kidney dysfunction or muscle injury. This test helps monitor kidney health.

24 services12 patients

Total protein level, urine 84156

The Total Protein Level in urine test measures the amount of protein present in your urine. This helps to check kidney health as high levels may indicate a problem. It's a simple, non-invasive procedure involving a urine sample.

23 services12 patients

New patient office or other outpatient visit with a high level of medical decision making, if using time, 60 minutes or more 99205

This is a first-time patient visit where a healthcare professional spends 60-74 minutes with you. It involves a comprehensive evaluation, including your medical history and current health condition. They'll also advise on preventive health measures and formulate a treatment plan if needed.

20 services20 patients

Body fluid cell count with cell identification 89051

Body fluid cell count with cell identification is a lab test that examines a sample of your body fluid. It helps to detect abnormal cells and count the number of different cell types. This can aid in diagnosing various conditions and monitor your health.

19 services13 patients

Crystal identification from tissue or body fluid 89060

Crystal identification from tissue or body fluid is a medical test that helps identify the presence of certain substances in the body. It involves analyzing samples from your body to detect crystals that may indicate health conditions like gout or kidney stones.

19 services13 patients

Administration of influenza virus vaccine G0008

The administration of the influenza virus vaccine, also known as the flu shot, is a simple procedure to protect against the flu. A healthcare provider injects a small dose of the vaccine into your arm. This stimulates your immune system to produce antibodies, which will help your body fight off the flu if exposed.

19 services19 patients

Screening test for pathogenic organisms 87081

A screening test for pathogenic organisms is a routine check-up procedure. It helps to identify harmful microorganisms in your body that can cause diseases. This involves collecting a sample like blood, saliva, or tissue, which is then examined in a lab for signs of these organisms.

18 services13 patients

Influenza vaccine, inactivated 90653

The Influenza vaccine, inactivated, is a shot given to protect against the flu. It contains killed virus particles that help your body build immunity to the flu. It's recommended annually to keep your protection up-to-date. It's safe for ages 6 months and up.

18 services18 patients

Injection into tendon or ligament 20550

An injection into a tendon or ligament involves placing medication directly into these areas to help reduce inflammation and pain. It's often used for conditions like arthritis or tendonitis. The procedure is quick and usually involves a local anesthetic.

17 services13 patients

Thyroxine (thyroid chemical), free 84439

The Thyroxine (thyroid chemical), free test is a blood test that measures the level of free T4 in your body. T4 is a hormone produced by your thyroid gland and is essential for growth and metabolism. If your T4 levels are too high or too low, it could indicate a thyroid disorder.

17 services14 patients

Blood test, thyroid stimulating hormone (tsh) 84443

A TSH blood test measures the level of thyroid stimulating hormone in your body. This hormone is produced by the pituitary gland and regulates how your thyroid works. It's a simple procedure where a small amount of blood is drawn from your arm for analysis.

17 services14 patients

Protein measurement, serum 84165

A serum protein measurement is a blood test that determines the levels of proteins in your blood. It is used to evaluate your overall health, and diagnose nutritional problems, kidney disease, liver disease, or immune disorders.

16 services16 patients

Injection, methylprednisolone acetate, 40 mg J1030

Methylprednisolone acetate is a medication given through an injection. It's a type of corticosteroid, which reduces inflammation and immune responses. It can be used to treat various conditions like arthritis, allergies, and skin diseases. This dose is 40 mg.

16 services13 patients

Blood test, lipids (cholesterol and triglycerides) 80061

A lipid panel is a blood test that measures fats and fatty substances, such as cholesterol and triglycerides. These substances are used by your body as a source of energy. High levels can lead to health issues, including heart disease.

14 services11 patients

Aspiration and/or injection of fluid from small joint using ultrasound guidance 20604

This procedure involves using ultrasound to accurately locate a small joint. A needle is then carefully inserted to remove fluid (aspiration) or inject medication. This can help diagnose or treat joint issues. It's generally safe and minimally invasive.

13 services12 patients

Aspiration and/or injection of fluid from large joint 20610

This procedure involves using a needle to remove (aspiration) or introduce (injection) fluid into a large joint like the knee or hip. It can help diagnose conditions, relieve discomfort, or deliver medication directly to the joint.

12 services11 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Virginia Hospital Center

Acute Care Hospitals · Arlington, VA

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number490050

Location1701 North George Mason DriveArlington, VA 22205 · Arlington County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 20006 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient

$147.85 typical visit price

range $65.18 – $194.86

Typical copayment $36.96 (range $16.29 – $48.71)

Most-billed visit code 99204

Established Patient

$113.72 typical visit price

range $21.40 – $158.88

Typical copayment $28.43 (range $5.35 – $39.72)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

77.12/100

MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program

Scored as part of a group practice

Promoting Interoperability

100

Improvement Activities

Cost

23.74

Referred Medical Equipment & Supplies CMS DME claims

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Neuromuscular stimulator, electronic shock unit E0745

DME-Other DME · category DE000N

1 supplier11 claims11 services$67.54 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. STEVEN MACHT MD

Surgery (Plastic and Reconstructive Surgery)

2021 K ST NW, #217
WASHINGTON, DC 20006

District of Columbia (202) 887-8120

ALAN W STONE MD

Internal Medicine

2021 K ST NW, SUITE 404
WASHINGTON, DC 20006

District of Columbia (202) 466-8118

KIMBERLY SUZANNE MOON MD

Obstetrics & Gynecology (Reproductive Endocrinology)

2021 K ST NW, SUITE 701
WASHINGTON, DC 20006

District of Columbia (202) 296-2595

DR. MARC JAY HOLZMAN M.D.

Ophthalmology

2021 K ST NW, SUITE 416
WASHINGTON, DC 20006

District of Columbia (202) 296-1333

SOFT TOUCH DENTISTS PC

Dentist

2021 K ST NW, SUITE 103
WASHINGTON, DC 20006

District of Columbia (202) 333-3883

JEFFREY B SHERMAN MD

Internal Medicine

2021 K ST NW, SUITE 404
WASHINGTON, DC 20006

District of Columbia (202) 466-8118

DR. MICHAEL J SCHWARTZ M.D.

Internal Medicine (Gastroenterology)

2021 K ST NW, SUITE T-110
WASHINGTON, DC 20006

District of Columbia (202) 296-3449

DR. BARRY PASS DDS

Dentist (Oral and Maxillofacial Radiology)

2021 K ST NW, SUITE 200
WASHINGTON, DC 20006

District of Columbia (202) 293-9729

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Justin Peng's NPI number?

The NPI number for Justin Peng is 1538328141. It was assigned to this individual provider in the NPPES registry on June 9, 2008.

Where is Justin Peng located?

Justin Peng practices at 2021 K St NW Suite 300, Washington, DC 20006. The listed phone number is (301) 942-7600.

What is Justin Peng's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Rheumatology, with taxonomy code 207RR0500X.

Is Justin Peng enrolled in Medicare?

Yes. Justin Peng is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organization bills Medicare for Justin Peng's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Justin Peng reassigns Medicare benefits to Arthritis And Rheumatism Associates PC (Rockville, MD). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Justin Peng's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is Justin Peng affiliated with any hospitals?

According to CMS data, Justin Peng is affiliated with Virginia Hospital Center.

When was this NPI record last updated?

The NPPES record for Justin Peng was last updated on February 5, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.