DR. PHILIP LOUIS MARJON M.D.
NPI 1912234121
Internal Medicine - Hematology & Oncology in San Marcos, CA

Q: What is Philip Marjon's NPI number?

The NPI number for Philip Marjon is 1912234121. It was assigned to this individual provider in the NPPES registry on November 9, 2009.

Q: What is Philip Marjon's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology & Oncology, with taxonomy code 207RH0003X.

Q: When was this NPI record last updated?

The NPPES record for Philip Marjon was last updated on December 22, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 7 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 November 09, 2009PECOS EnrolledAccepts Medicare Assignment

838 NORDAHL RD STE 300, SAN MARCOS, CA 92069(760) 747-8935(760) 466-0078 Get Directions Write a Review

NPPES record last updated: December 22, 2025. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Dec 22, 2025, Feb 27, 2025, Feb 5, 2024 and 6 more (9 updates tracked since 2018).

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About Dr. Philip Louis Marjon M.d. NPPES

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

DR. PHILIP LOUIS MARJON M.D. (NPI 1912234121) is an individual hematology & oncology provider in San Marcos, California, licensed in California (C175032) and active in the NPI registry since November 2009. He is enrolled in Medicare PECOS, maintains 3 additional practice locations, and is a graduate of University Of New Mexico School Of Medicine (2007).

NPPES Registry Identity

NPI1912234121

Entity TypeIndividualMale

Primary Taxonomy207RH0003X

Provider Legal NameDR. PHILIP LOUIS MARJONCredential: M.D.

Location Address838 NORDAHL RD STE 300San Marcos, CA 92069-3599

Mailing Address104 Woodmont Blvd Ste 500Nashville, TN 37205-2245 · (615) 783-1066

Phone(760) 747-8935

Fax(760) 466-0078

Sole ProprietorYes

Medical School CMSUniversity Of New Mexico School Of MedicineGraduated 2007

Enumeration DateNovember 9, 2009

Last NPPES UpdateDecember 22, 20259 updates tracked since enumeration

NPPES CertifiedDecember 22, 2025

✔ NPI 1912234121 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Hematology & OncologyAllopathic & Osteopathic Physicians

Taxonomy Code207RH0003X

License✔ Licensed in CA · C175032

Definition

An internist doctor of osteopathy that specializes in the treatment of the combination of hematology and oncology disorders. A doctor of osteopathy that is board eligible/certified by the American Osteopathic Board of Internal Medicine WAS able to obtain a Certificate of Special Qualifications in the field of Hematology and Oncology. The Certificate is NO longer offered.

838 NORDAHL RD STE 300, San Marcos, CA 92069

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Secondary Practice Locations 3

Location 1450 4th Ave Ste 311Chula Vista, CA 91910-4429 · Phone (619) 371-9156

Location 228078 Baxter Rd Ste 140Murrieta, CA 92563-1403 · Phone (760) 733-9191

Location 33965 5th Ave Ste 230San Diego, CA 92103-3107 · Phone (619) 872-0953 · Fax (619) 378-3162

Group Practice 1

Group TaxonomyThis provider is a business group of one or more individual practitioners, who practice with different areas of specialization.193200000X MULTI-SPECIALTY GROUP

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

Dr. Philip Louis Marjon M.d. 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 ID5991945693

PECOS Enrollment IDI20211029001903

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 36

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, darbepoetin alfa, 1 microgram (non-esrd use) J0881

Darbepoetin alfa injection is a medication used to treat anemia (low red blood cell count) often caused by chronic kidney disease or chemotherapy. It works by stimulating your body to produce more red blood cells, helping to increase your energy and well-being.

19,700 services36 patients

Injection, aprepitant, 1 mg J0185

Aprepitant injection is a medication used to prevent nausea and vomiting caused by chemotherapy. It works by blocking certain substances in the brain that trigger these symptoms. The dosage is based on your medical condition and response to treatment.

6,240 services18 patients

Injection, pembrolizumab, 1 mg J9271

Pembrolizumab is a medication given via injection to help your body's immune system fight certain types of cancer. It's typically administered in a hospital or clinic by a healthcare professional.

4,600 services11 patients

Injection, granisetron, extended-release, 0.1 mg J1627

Granisetron extended-release injection is a medication that helps prevent nausea and vomiting often caused by cancer treatments like chemotherapy. It's administered under the skin and slowly releases the drug over time to provide long-lasting effects.

4,300 services15 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.

4,080 services27 patients

Injection, dexamethasone sodium phosphate, 1 mg J1100

Dexamethasone sodium phosphate is a medication given via injection. It is a type of steroid that helps reduce inflammation and immune responses. It can be used to treat a variety of conditions, such as allergies, skin conditions, arthritis, and more.

1,680 services47 patients

Injection, leucovorin calcium, per 50 mg J0640

Leucovorin calcium is an injection given to enhance the effectiveness of certain cancer treatments or to reduce the harmful effects of some medications. The dose is determined by your doctor and is typically administered in a healthcare setting.

430 services12 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.

391 services249 patients

Injection, palonosetron hcl, 25 mcg J2469

Palonosetron HCL is an injection used to prevent nausea and vomiting caused by chemotherapy. It works by blocking a natural substance (serotonin) in the body that can cause vomiting. This helps improve your comfort during cancer treatment.

310 services17 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.

278 services104 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.

260 services128 patients

Injection, fluorouracil, 500 mg J9190

Fluorouracil is a chemotherapy drug, given as an injection to treat various types of cancer. The 500 mg dose helps to stop cancer cells from growing and multiplying. You might feel some side effects, but these are typically manageable.

252 services12 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.

250 services104 patients

Infusion into a vein for therapy, prevention, or diagnosis, additional sequential infusion, 1 hour or less 96367

This procedure involves injecting fluids or medication directly into your vein. It's used for treatment, prevention, or diagnosis. An additional sequential infusion may be given within an hour if needed. This helps to ensure the medicine is distributed effectively in your body.

190 services65 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.

183 services77 patients

Unclassified drugs J3490

Unclassified drugs are medications that don't fit into an existing category or class due to their unique properties or uses. They may be used for various conditions and their effects may differ widely. Always ask your healthcare provider for more information about these drugs.

124 services46 patients

Injection, diphenhydramine hcl, up to 50 mg J1200

Diphenhydramine HCL injection is a medicine given to alleviate symptoms of allergies, colds, or hay fever. It can also help with motion sickness and certain symptoms of Parkinson's disease. Up to 50 mg may be administered depending on your condition.

90 services37 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.

75 services66 patients

Fluorodeoxyglucose f-18 fdg, diagnostic, per study dose, up to 45 millicuries A9552

Fluorodeoxyglucose F-18 FDG is a radioactive drug used in PET scans. It helps doctors see how your tissues and organs are functioning. The drug is given in a specific dose, up to 45 millicuries, depending on your body size and the type of scan.

74 services68 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.

70 services17 patients

Administration of additional new drug or substance into vein, 1 hour or less 96417

This procedure involves introducing a new drug or substance into your vein, typically via an IV drip. It lasts for an hour or less. This method allows the substance to quickly reach your bloodstream, ensuring rapid and effective treatment.

67 services23 patients

Injection of additional new drug or substance into vein 96375

This procedure involves introducing a new medication or substance into your bloodstream via a vein. It's typically done using a small needle. The substance can help treat various conditions or assist in diagnostic procedures. It's generally safe and monitored by professionals.

65 services31 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.

65 services24 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.

54 services34 patients

Nuclear medicine study from skull base to mid-thigh with ct scan 78815

A nuclear medicine study from skull base to mid-thigh with a CT scan involves using a small amount of radioactive material and CT imaging to examine body tissues and organs. This helps detect any abnormalities by providing detailed images of the body's internal structure.

51 services45 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.

37 services34 patients

Nuclear medicine study whole body with ct scan 78816

A Nuclear Medicine Study with a CT Scan is a diagnostic procedure. It uses a small amount of radioactive substance and a CT scan to create detailed images of your body. These images help doctors diagnose, monitor, and treat various conditions.

29 services28 patients

Infusion into a vein for therapy, prevention, or diagnosis concurrent with another infusion 96368

An infusion into a vein is a method of delivering medication, nutrients, or fluids directly into your bloodstream. If it's concurrent with another infusion, it means two different solutions are given at the same time. This can be for treatment, prevention, or diagnostic purposes.

28 services13 patients

Administration of prolonged chemotherapy into vein 96416

Chemotherapy is a treatment using drugs to destroy cancer cells. Prolonged chemotherapy into a vein involves the slow infusion of these drugs directly into your bloodstream over an extended period. This method ensures a continuous and effective dose to combat your cancer cells.

26 services11 patients

Infusion into a vein for therapy, prevention, or diagnosis, each additional hour 96366

This procedure involves delivering medication, fluids, or nutrients directly into your vein. This is done to treat, prevent, or diagnose various conditions. Each additional hour refers to the extended time you may need to receive these substances for optimal results.

23 services15 patients

Administration of additional new drug or substance into vein using push technique 96411

This procedure involves injecting a new medication or substance directly into your vein using a method called the 'push' technique. It's a quick way to deliver medication into your bloodstream for fast-acting relief or treatment.

22 services11 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.

22 services22 patients

Injection, vitamin b-12 cyanocobalamin, up to 1000 mcg J3420

This is a procedure where a small dose of Vitamin B-12, also known as Cyanocobalamin, is injected into your body. This vitamin is essential for nerve function and the production of red blood cells. It's often used to treat vitamin B-12 deficiency.

21 services13 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.

19 services19 patients

Administration of hormonal anti-neoplastic chemotherapy under skin or into muscle 96402

This procedure involves the injection of hormone-based anti-cancer drugs under the skin or into a muscle. These medications help to slow down or stop the growth of certain types of cancer cells. The process is usually quick and can be performed in a clinic or hospital.

18 services14 patients

Telephone medical discussion with physician, 11-20 minutes 99442

This is a service where you have a phone conversation with your doctor for 11-20 minutes. It's used for discussing health concerns, reviewing test results, or managing ongoing conditions. It's a convenient way to receive medical advice without an in-person visit.

13 services11 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 92069 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

$184.71 typical visit price

range $62.10 – $184.71

Typical copayment $46.17 (range $15.52 – $46.17)

Most-billed visit code 99205

Established Patient

$108.42 typical visit price

range $20.62 – $151.42

Typical copayment $27.10 (range $5.15 – $37.85)

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 7

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

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