GREGORY A. JOHNSON MD
NPI 1942213509
Internal Medicine in Somerville, MA

Q: What is Gregory Johnson's NPI number?

The NPI number for Gregory Johnson is 1942213509. It was assigned to this individual provider in the NPPES registry on August 14, 2006.

Q: What is Gregory Johnson's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Q: When was this NPI record last updated?

The NPPES record for Gregory Johnson was last updated on February 18, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 years 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 August 14, 2006PECOS EnrolledAccepts Medicare Assignment

40 HOLLAND ST, HARVARD VANGUARD MEDICAL ASSOCIATES, SOMERVILLE, MA 02144(617) 629-6350 Get Directions Write a Review

NPPES record last updated: February 18, 2021. Verified against the NPPES registry weekly; last sync: August 02, 2026.

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About Gregory A. Johnson Md NPPES

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

GREGORY A. JOHNSON MD (NPI 1942213509) is an individual internal medicine provider in Somerville, Massachusetts, licensed in Massachusetts (151587) and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS, is affiliated with Northeast Hospital Corporation, and is a graduate of Warren Alpert Medical School Of Brown University (1993).

NPPES Registry Identity

NPI1942213509

Entity TypeIndividualMale

Primary Taxonomy207R00000X

Provider Legal NameGREGORY A. JOHNSONCredential: MD

Location Address40 HOLLAND ST, HARVARD VANGUARD MEDICAL ASSOCIATESSomerville, MA 02144-2705

Mailing Address40 Holland St, Harvard Vanguard Medical AssociatesSomerville, MA 02144-2705 · (617) 629-6350

Phone(617) 629-6350

Sole ProprietorNo

Medical School CMSWarren Alpert Medical School Of Brown UniversityGraduated 1993

Enumeration DateAugust 14, 2006

Last NPPES UpdateFebruary 18, 2021

NPPES CertifiedFebruary 18, 2021

✔ NPI 1942213509 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in MA · 151587

Definition

A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.

40 HOLLAND ST, Somerville, MA 02144

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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Gregory A. Johnson 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 ID2264452523

PECOS Enrollment IDI20051201000118

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.

Areas of Expertise CMS Part B claims 24

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.

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.

447 services344 patients

Detection test by immunoassay with direct visual observation for influenza virus 87804

This is a test that identifies the influenza virus in your body. It works by using an immunoassay, a method that detects the presence of the virus through an immune response. The results are directly observable, making it a quick and efficient way to diagnose flu.

338 services81 patients

Detection test by immunoassay technique for severe acute respiratory syndrome coronavirus 87426

An immunoassay test for severe acute respiratory syndrome coronavirus is a diagnostic tool. It uses your body's immune response to detect the presence of the virus. It involves taking a sample, usually from your nose or throat, which is then analyzed in a lab for signs of the virus.

166 services77 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.

132 services122 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.

128 services127 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.

105 services103 patients

Amplifed dna or rna probe detection of severe acute respiratory syndrome coronavirus 2 (covid-19) antigen 87635

This is a lab test that detects the presence of COVID-19 in your body. It uses a technique to amplify the virus's genetic material, either DNA or RNA, making it easier to identify. A positive result indicates an active infection.

104 services69 patients

Blood test panel for electrolytes (sodium potassium, chloride, carbon dioxide) 80051

A blood test panel for electrolytes checks the levels of sodium, potassium, chloride, and carbon dioxide in your blood. These elements are crucial for body functions such as maintaining fluid balance, muscle contractions, and heart rhythm. The test helps identify any imbalances.

80 services77 patients

Urea nitrogen level to assess kidney function, quantitative 84520

The urea nitrogen level test is a routine blood test that checks the amount of urea nitrogen in your blood to evaluate how well your kidneys are working. If the levels are higher than normal, it may indicate that your kidneys are not functioning properly.

80 services77 patients

Blood creatinine level 82565

A blood creatinine level test measures the amount of creatinine in your blood. Creatinine is a waste product that your body produces when it uses energy. High levels may indicate that your kidneys aren't working properly. This test is often used to monitor kidney health.

79 services76 patients

Urinalysis, manual test 81002

A urinalysis is a simple, non-invasive test that checks the urine for various elements such as sugar, protein, and signs of infection. It can help detect many common conditions, including kidney disease and diabetes. The manual test involves a lab technician examining a urine sample.

63 services61 patients

Blood glucose (sugar) level 82947

A blood glucose level test measures the amount of sugar in your blood. It's often used to monitor and manage conditions like diabetes. High or low levels can indicate a health issue. The test is usually done by pricking your finger for a small blood sample.

61 services60 patients

Injection, ceftriaxone sodium, per 250 mg J0696

Ceftriaxone sodium is an antibiotic injection used to treat a variety of bacterial infections. Each injection contains 250 mg of the medicine. It works by stopping the growth of bacteria in your body.

60 services14 patients

Bacterial colony count, urine 87086

A bacterial colony count, urine, is a laboratory test that checks a urine sample for bacteria. It helps to identify if an infection is present in the urinary system. High numbers of bacteria in the urine can indicate a urinary tract infection (UTI).

57 services55 patients

Established patient office or other outpatient visit with straightforward medical decision making, if using time, 10 minutes or more 99212

This is a routine check-up for patients who have previously seen the doctor. During this 10-19 minute visit, the doctor will review your health status, discuss any concerns, and manage ongoing treatments or medications. It's a chance to ensure your health is on track.

40 services37 patients

Detection test by immunoassay with direct visual observation for streptococcus, group a (strep) 87880

A detection test by immunoassay for Group A Strep is a quick procedure to identify a bacterial infection in your throat. It involves taking a throat swab and applying it to a test strip, which changes color if Strep bacteria are present.

31 services28 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.

28 services28 patients

Bacterial culture for aerobic isolates 87077

A bacterial culture for aerobic isolates is a lab test that helps identify bacteria that thrive in oxygen-rich environments. A sample from the suspected infection site is collected, then placed in a special medium that promotes bacterial growth. After a set period, the lab identifies any bacteria present, aiding in accurate diagnosis and treatment.

28 services24 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.

24 services24 patients

Evaluation of antimicrobial drug (antibiotic, antifungal, antiviral), microdilution or agar dilution 87186

This process checks how well certain drugs, like antibiotics, can fight against infections. It involves mixing the drug with a microbe (like bacteria or a virus) in a lab. By observing how the microbe reacts, it helps determine the best drug to treat your infection.

22 services19 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.

20 services20 patients

Natriuretic peptide (heart and blood vessel protein) level 83880

A natriuretic peptide level test is a blood test that helps doctors check for heart failure. It measures the amount of certain proteins that your heart and blood vessels produce when they are under stress. High levels may indicate heart disease.

17 services17 patients

Coagulation function measurement, d-dimer; quantitative 85379

A quantitative D-dimer test measures the amount of D-dimer, a protein fragment, in your blood. This test helps detect abnormal blood clotting. D-dimer levels can rise in conditions where clots are forming and breaking down, such as deep vein thrombosis or pulmonary embolism.

13 services13 patients

Red blood cell sedimentation rate, to detect inflammation, non-automated 85651

The Red Blood Cell Sedimentation Rate test measures how quickly red blood cells settle at the bottom of a test tube. If they settle faster than normal, it may indicate inflammation in the body. This test is non-automated, meaning it's manually performed by a lab technician.

11 services11 patients

Hospital Affiliations CMS Care Compare

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

Northeast Hospital Corporation

Acute Care Hospitals · Beverly, MA

3/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number220033

Location85 Herrick StreetBeverly, MA 01915 · Essex County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 02144 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

$144.11 typical visit price

range $63.72 – $189.86

Typical copayment $36.02 (range $15.93 – $47.46)

Most-billed visit code 99204

Established Patient

$111.18 typical visit price

range $21.07 – $155.29

Typical copayment $27.79 (range $5.26 – $38.82)

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.

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.

ELIZABETH AHLBORN NECHEV

Nurse Practitioner

40 HOLLAND ST
SOMERVILLE, MA 02144

Middlesex County (617) 657-6445

HENRY W STOLL PA

Physician Assistant (Medical)

40 HOLLAND ST
SOMERVILLE, MA 02144

Middlesex County (617) 629-6000

D. SCOTT GILBERT PA-C

Physician Assistant

40 HOLLAND ST
SOMERVILLE, MA 02144

Middlesex County (617) 654-7111

STEPHANIE E. NEALY RD, LDN

Dietitian, Registered

40 HOLLAND ST, NUTRITION
SOMERVILLE, MA 02144

Middlesex County (617) 629-6444

MARIA ELIZABETH HEDBERG FNP

Nurse Practitioner (Family)

40 HOLLAND ST
SOMERVILLE, MA 02144

Middlesex County (617) 629-6000

MRS. ANNETTE OHEARN 5532-DO-DO

Technician/Technologist (Optician)

40 HOLLAND ST
SOMERVILLE, MA 02144

Middlesex County (617) 629-6378

SHEENA ANN FREMAULT MACEDO FNP-C

Nurse Practitioner

40 HOLLAND ST
SOMERVILLE, MA 02144

Middlesex County (617) 629-6032

RICHARD MICHALOWSKI DMD

Dentist (General Practice)

40 HOLLAND ST
SOMERVILLE, MA 02144

Middlesex County (617) 629-6080

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 Gregory Johnson's NPI number?

The NPI number for Gregory Johnson is 1942213509. It was assigned to this individual provider in the NPPES registry on August 14, 2006.

Where is Gregory Johnson located?

Gregory Johnson practices at 40 Holland St Harvard Vanguard Medical Associates, Somerville, MA 02144. The listed phone number is (617) 629-6350.

What is Gregory Johnson's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Gregory Johnson enrolled in Medicare?

Yes. Gregory Johnson 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.

Is Gregory Johnson affiliated with any hospitals?

According to CMS data, Gregory Johnson is affiliated with Northeast Hospital Corporation.

When was this NPI record last updated?

The NPPES record for Gregory Johnson was last updated on February 18, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 years 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.