Medicare Enrolled
Dr. Arash Horizon, M.D.
Rheumatology · Los Angeles, CA
Practice pattern: Mixed Practice
— Diverse clinical practice across multiple procedure types
Low-engagement
Very High
DATA COVERAGE
Data in 4 of 4 federal sources
Measures public federal data availability — not provider quality
Informational, not a quality rating.
This page presents federal public records about Dr. Horizon from CMS (NPPES, Open Payments, Medicare Provider Utilization, PECOS). It is not medical advice, an endorsement, or a judgment of clinical quality. Always consult the provider directly and a licensed clinician for medical decisions. Read methodology →
Are you Dr. Horizon?
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What this data tells you about Dr. Horizon
Dr. Arash Horizon is a rheumatology specialist in Los Angeles, CA, with 20 years of NPI registration. Based on federal Medicare data, Dr. Horizon performed 428,872 Medicare services across 12,860 unique beneficiaries.
Between the years covered by Open Payments, Dr. Horizon received a total of $2,279 from 18 pharmaceutical and/or device companies across 106 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common in rheumatology. Most payments are for meals and travel — low-value interactions common across virtually all practicing physicians. Patients may wish to discuss these relationships with their provider.
The Data Coverage level for Dr. Horizon is Very High — reflecting how much public federal data is available about this provider. Patients are encouraged to use this data as one of several factors when choosing a healthcare provider.
✓ 20 years in practice
▲ Top 1% volume in CA
$2,279 industry payments
Medicare Practice Summary
Medicare Utilization ↗428,872
Medicare services
Top 1% in CA for rheumatology
12,860
Unique beneficiaries
$11
Avg. Medicare payment
Medicare patients only (65+ / disabled) · How to read this →
~21,444 Medicare services per year of practice
Top procedures by volume
Ranked by number of services performed for Medicare patients. Avg. submitted charge is what the provider billed; avg. Medicare payment is what CMS paid.
| Procedure | Volume | Avg. paid | Avg. submitted |
|---|---|---|---|
| Certolizumab injection (Cimzia) An injection of certolizumab pegol administered under the direct supervision of a physician. |
138,000 | $4 | $12 |
| Romosozumab injection (Evenity) for osteoporosis | 53,760 | $8 | $24 |
| Iron infusion (Injectafer) An intravenous injection of ferric carboxymaltose, an iron replacement medication. |
51,000 | $1 | $5 |
| Tocilizumab injection (Actemra) | 47,280 | $5 | $9 |
| Vedolizumab infusion (Entyvio) This procedure involves the administration of vedolizumab via injection. The dosage is measured in milligrams. |
22,800 | $17 | $65 |
| Golimumab infusion (Simponi Aria) Administration of golimumab medication directly into a vein. This code specifies the dosage amount of 1 milligram for intravenous delivery. |
17,008 | $11 | $60 |
| Injection, immune globulin (bivigam), 500 mg | 11,670 | $56 | $150 |
| Infliximab infusion (Remicade) An injection of infliximab, excluding biosimilar versions, administered in a 10 mg dose. |
10,582 | $26 | $100 |
| Denosumab injection (Prolia/Xgeva) | 9,424 | $18 | $55 |
| Omalizumab injection (Xolair) for asthma/allergy | 8,400 | $30 | $40 |
| Ustekinumab, for intravenous injection, 1 mg | 7,153 | $10 | $45 |
| Privigen immune globulin injection, 500 mg An intravenous injection of Privigen, a non-lyophilized immune globulin product, administered in a 500 mg dose. |
5,730 | $37 | $75 |
| Abatacept infusion (Orencia) An injection of abatacept administered under the direct supervision of a physician. This code is used for Medicare when the drug is not self-administered. |
5,600 | $34 | $100 |
| Immunoglobulin level test A blood test that measures the level of gammaglobulins, which are immune system proteins. |
3,756 | $9 | $35 |
| Rituximab biosimilar injection, 10 mg An injection of rituximab-abbs, a biosimilar medication, administered in a 10 mg dose. |
2,808 | $34 | $100 |
| Rituximab injection, 10 mg Administration of a 10 mg dose of rituximab medication via injection. |
2,410 | $64 | $225 |
| Steroid injection (triamcinolone) A 10 mg injection of triamcinolone acetonide, a corticosteroid medication. This code specifies the drug and dosage administered. |
1,834 | $1 | $10 |
| Blood draw (venipuncture) Insertion of a needle into a vein to collect a blood sample. |
1,779 | $8 | $15 |
| Non-hormonal chemotherapy injection This procedure involves administering non-hormonal anti-neoplastic chemotherapy medication via injection into the skin or muscle tissue. |
1,705 | $68 | $185 |
| C-reactive protein test (inflammation marker) A blood test that measures the level of C-reactive protein to detect the presence of infection or inflammation in the body. |
1,695 | $5 | $42 |
| Erythrocyte sedimentation rate (ESR) test A blood test that measures how quickly red blood cells settle in a test tube to detect inflammation in the body. This specific method is performed manually rather than using an automated machine. |
1,693 | $4 | $15 |
| Complete blood count (CBC) with differential An automated laboratory test that measures the levels of red blood cells, white blood cells, and platelets in the blood, including a breakdown of the different types of white blood cells. |
1,685 | $8 | $45 |
| Comprehensive metabolic blood panel A blood test that measures a group of chemicals, including glucose, electrolytes, and kidney and liver function markers. |
1,684 | $10 | $105 |
| Complement function test A blood test that measures the activity of complement proteins, which are part of the immune system. |
986 | $12 | $42 |
| Complement and antigen measurement A laboratory test to measure levels of complement proteins and antigens in the blood. |
984 | $12 | $51 |
| Office visit, established patient (30-39 min) A follow-up office visit for an existing patient lasting between 30 and 39 minutes. The visit involves medical evaluation and management of the patient's condition. |
963 | $105 | $375 |
| Additional hour of intravenous chemotherapy This code represents the administration of chemotherapy medication into a vein for each additional hour beyond the initial period. |
901 | $26 | $195 |
| COVID-19 antibody test A blood test that measures antibodies to severe acute respiratory syndrome coronavirus 2 (COVID-19). It detects the presence of immune response markers to the virus. |
884 | $41 | $90 |
| Autoimmune disorder antibody test A laboratory test that measures antibodies in the blood to help assess for autoimmune disorders. |
859 | $17 | $82 |
| Office visit, established patient (10-19 min) An office visit for an existing patient lasting 10 to 19 minutes. The visit involves medical evaluation and management of the patient's condition. |
803 | $48 | $125 |
| Intravenous drug injection A procedure involving the administration of a medication or substance directly into a vein. |
788 | $35 | $150 |
| Intravenous injection of additional new drug or substance Administration of an additional new medication or substance directly into a vein. |
752 | $14 | $150 |
| Intravenous chemotherapy infusion, 1 hour or less Administration of chemotherapy medication directly into a vein. The procedure takes one hour or less to complete. |
643 | $119 | $524 |
| Normal saline infusion, 250 cc Administration of 250 cubic centimeters of normal saline solution into a vein. This procedure involves the intravenous delivery of a sterile saltwater fluid. |
593 | $1 | $45 |
| Additional hour of intravenous infusion This code represents each additional hour of intravenous infusion beyond the initial hour for therapy, prevention, or diagnosis. |
572 | $19 | $150 |
| Drug injection, under skin or into muscle A procedure involving the administration of a medication or substance via injection into the subcutaneous tissue or muscle. |
539 | $12 | $65 |
| Vitamin D level test A blood test to measure the amount of Vitamin D-3 in your body. |
529 | $29 | $99 |
| Office visit, established patient, complex (40-54 min) An office or outpatient visit for an existing patient lasting between 40 and 54 minutes. This level of service is determined by the total time spent on the date of the encounter. |
518 | $149 | $325 |
| Normal saline infusion, 500 ml Administration of sterile normal saline solution through an intravenous line. This procedure involves the infusion of a 500 ml unit of the solution. |
485 | $1 | $45 |
| Tuberculosis test, enumeration of t-cells A blood test that counts T-cells to help detect tuberculosis infection. |
385 | $98 | $205 |
| Vitamin B-12 level test A blood test that measures the amount of vitamin B-12 in your body. |
384 | $15 | $30 |
| DNA antibody test (native or double-stranded) A blood test that measures the level of antibodies targeting native or double-stranded DNA. This test is used to detect the presence of these specific antibodies in the body. |
373 | $13 | $42 |
| X-ray of hand, minimum of 3 views An X-ray imaging test of the hand that captures at least three different angles to visualize the bones and joints. |
372 | $35 | $126 |
| Wrist X-ray, minimum 3 views An imaging test using X-rays to capture at least three different angles of the wrist bones and joints. |
363 | $38 | $125 |
| Intravenous infusion, 1 hour or less Administration of medication or fluid directly into a vein for therapeutic, preventive, or diagnostic purposes. The procedure lasts one hour or less. |
336 | $60 | $250 |
| Office visit, established patient (20-29 min) An office visit for an existing patient lasting between 20 and 29 minutes. The visit involves medical evaluation and management of the patient's condition. |
307 | $75 | $150 |
| Foot X-ray, 3+ views An X-ray imaging test of the foot that captures at least three different views to evaluate the bones and joints. |
297 | $32 | $126 |
| Parathyroid hormone level test A blood test that measures the amount of parathyroid hormone in your body. This hormone helps regulate calcium levels in the blood and bones. |
282 | $40 | $115 |
| Iron binding capacity test A blood test that measures the amount of iron in the blood and the blood's ability to bind and transport iron. |
274 | $9 | $45 |
| Ferritin level test (iron stores) A blood test that measures the level of ferritin, a protein that stores iron in the body. |
273 | $13 | $60 |
| Iron level test | 273 | $6 | $25 |
| Cardiac enzyme level (CK-MB) test A blood test that measures the total level of creatine kinase, specifically the cardiac enzyme fraction, to help evaluate heart muscle damage. |
262 | $6 | $40 |
| Immunoassay substance measurement A laboratory test that uses immunoassay techniques to measure the level of a specific substance in a sample. |
237 | $17 | $52 |
| Uric acid level test A blood test that measures the level of uric acid in your body. Uric acid is a waste product formed when the body breaks down purines. |
223 | $4 | $35 |
| Joint injection, major joint Removal of fluid from a large joint and/or injection of medication into the joint space. |
172 | $55 | $175 |
| Telephone medical discussion, 11-20 minutes A phone conversation with a physician lasting between 11 and 20 minutes. |
160 | $59 | $125 |
| Knee X-ray, 3 views An X-ray imaging test of the knee joint that captures three different angles to evaluate the bones and surrounding structures. |
141 | $37 | $125 |
| Vitamin B-12 injection An injection of vitamin B-12 (cyanocobalamin) with a dose of up to 1000 mcg. |
141 | $1 | $40 |
| Influenza vaccine, quadrivalent, 0.5 ml dosage | 120 | $20 | $30 |
| Flu vaccine administration This procedure involves the administration of the influenza virus vaccine. It covers the process of delivering the vaccine to the patient. |
117 | $34 | $40 |
| X-ray of lower and sacral spine, minimum of 4 views An X-ray imaging test of the lower back and sacrum using at least four different angles to visualize the bones and joints. |
114 | $48 | $145 |
| Glutamyltransferase (GGT) level test A blood test that measures the level of the liver enzyme glutamyltransferase (GGT) to help evaluate liver health. |
109 | $7 | $45 |
| Antineutrophil cytoplasmic antibody titer | 108 | $12 | $20 |
| Zoledronic acid injection, 1 mg An injection of zoledronic acid administered at a dose of 1 mg. |
103 | $7 | $74 |
| Telephone medical discussion, 5-10 minutes A phone conversation with a physician lasting between 5 and 10 minutes to discuss medical matters. |
101 | $33 | $100 |
| Bone density scan (DEXA) A test that uses low-dose X-rays to measure bone mineral density in the hip, pelvis, and spine. It helps assess bone strength and risk of fractures. |
92 | $45 | $248 |
| White blood cell antibody identification test A laboratory test used to identify specific antibodies present in the blood that target white blood cells. |
92 | $14 | $51 |
| Rheumatoid arthritis antibody test A blood test to measure antibodies used in assessing rheumatoid arthritis. |
87 | $13 | $39 |
| Hemoglobin a1c level, by device for home use | 78 | $10 | $42 |
| Rheumatoid factor level | 78 | $5 | $14 |
| Additional hour of intravenous hydration This code represents each additional hour of intravenous fluid administration beyond the initial hour. It is used to bill for extended hydration therapy. |
72 | $12 | $100 |
| X-ray of sacroiliac joint, 1-2 views An X-ray imaging test of the joint connecting the lower spine to the hip bone, using one to two images. |
68 | $31 | $125 |
| New patient office visit, complex (60-74 min) | 63 | $185 | $575 |
| Shoulder X-ray, 2+ views An X-ray imaging test of the shoulder joint using at least two different angles to visualize the bones and surrounding structures. |
60 | $33 | $125 |
| Lipid panel (cholesterol and triglycerides) A blood test that measures cholesterol and triglyceride levels. |
60 | $13 | $70 |
| Thyroid stimulating hormone (TSH) test A blood test that measures the level of thyroid stimulating hormone to evaluate thyroid function. |
60 | $16 | $65 |
| Total cortisol level test A blood test that measures the total amount of cortisol hormone in your body. Cortisol is a hormone produced by the adrenal glands. |
58 | $16 | $56 |
| Intravenous hydration infusion, 31-60 minutes Administration of fluids into a vein to maintain hydration. This procedure involves an infusion lasting between 31 and 60 minutes. |
57 | $30 | $100 |
| Prolonged office E/M service, first 15 minutes This code is used for additional time spent by a physician beyond the maximum required time of a primary office or outpatient evaluation and management service. It is billed in 15-minute increments based on total time spent on the date of the primary service. |
56 | $27 | $135 |
| Autoimmune disorder antibody titer test A blood test that measures the level of specific antibodies to help assess autoimmune disorders. |
47 | $11 | $25 |
| X-ray of upper spine, 6 or more views An X-ray imaging test of the upper spine using six or more separate views to capture detailed images of the bones and structures in that area. |
41 | $57 | $175 |
| Amylase enzyme level test A blood test that measures the amount of amylase, an enzyme produced by the pancreas and salivary glands, to help evaluate pancreatic health. |
38 | $6 | $20 |
| Folic acid level test A blood test that measures the amount of folic acid in the serum. |
38 | $14 | $30 |
| Joint fluid aspiration or injection, small joint Removal of fluid from a small joint or injection of medication into a small joint. |
37 | $37 | $125 |
| Thyroxine (T4) level test A blood test that measures the total amount of thyroxine, a thyroid hormone, in your body. |
35 | $7 | $45 |
| Methylprednisolone injection, up to 125 mg An injection of methylprednisolone sodium succinate, a corticosteroid medication, with a dosage of up to 125 mg. |
34 | $4 | $17 |
| Hip X-ray, 1 view An X-ray image of the hip joint taken from a single angle to visualize the bones and surrounding structures. |
30 | $31 | $125 |
| Autoimmune disorder screening test A laboratory test used to screen for the presence of autoimmune disorders. |
30 | $11 | $25 |
| Hyaluronan gel injection for joint An injection of hyaluronan gel into a joint to supplement joint fluid. This procedure is administered as a single dose. |
29 | $406 | $1,259 |
| Pneumococcal conjugate vaccine (PCV20) An intramuscular injection of the 20-valent pneumococcal conjugate vaccine. It is used to protect against diseases caused by Streptococcus pneumoniae bacteria. |
26 | $281 | $650 |
| Hemoglobin A1c test (diabetes monitoring) A blood test that measures your average blood sugar levels over the past two to three months. |
25 | $10 | $35 |
| Pneumonia vaccine administration This procedure involves the injection of a vaccine to protect against pneumococcal disease. It is administered by a healthcare provider. |
25 | $34 | $39 |
| Lipase level test A blood test that measures the amount of lipase, a fat-digesting enzyme, in your body. |
22 | $7 | $20 |
| PSA test (prostate cancer screening) | 21 | $17 | $65 |
| Telephone medical discussion, 21-30 minutes A telephone conversation with a physician lasting between 21 and 30 minutes. This code covers the time spent discussing medical matters over the phone. |
21 | $86 | $173 |
| Joint fluid aspiration or injection, medium joint Removal of fluid from a medium-sized joint or injection of medication into the joint space. |
20 | $48 | $145 |
| Manual urinalysis with microscopic examination A urine test performed manually without automated equipment. The sample is examined under a microscope to check for abnormalities. |
20 | $4 | $35 |
| Sex hormone binding globulin level test A blood test that measures the level of sex hormone binding globulin, a protein that binds to sex hormones in the bloodstream. |
15 | $20 | $64 |
| Total testosterone level test A blood test that measures the total amount of testosterone in your body. This hormone is important for various bodily functions in both men and women. |
15 | $24 | $72 |
| X-ray of sacroiliac joint, 3 or more views An X-ray imaging test that takes three or more pictures of the joint connecting the lower spine to the hip bone. |
14 | $37 | $145 |
| Bone density scan (DEXA) of hip, pelvis, and spine This test measures bone density in the hip, pelvis, and spine to assess bone strength. It also includes an assessment for spine fractures. |
14 | $61 | $125 |
| Magnesium level test A blood test to measure the amount of magnesium in your body. This helps check for magnesium deficiency or excess. |
12 | $7 | $20 |
How to read this data: This reflects Medicare patients only (typically 65+). Payment amounts are what Medicare paid the provider, not your out-of-pocket cost. A higher procedure volume generally indicates more experience with that procedure.
25.6% high complexity
68.5% medium
5.9% routine
Industry Payment Transparency
Open Payments through 2024 ↗$2,279
Total received (2018-2024)
Avg $326/year across 7 years
Top 49% in CA for rheumatology
A higher payment rank reflects disclosed industry relationships (consulting, research, speaking) common among subspecialists — not wrongdoing.
18
Companies
106
Individual payments
All payments are legal and publicly reported · Not evidence of wrongdoing · How to interpret →
Payment profile
Industry payments classified by relationship type. Not all payments are equal — research and consulting reflect different relationships than speaking programs or meals.
Meals & Travel
Food, beverages, travel, and lodging — typically low-value
$2,279 (100.0%)
Payment trend by year
Annual totals from pharmaceutical and medical device companies.
2024
$38
2023
$139
2022
$120
2021
$23
2020
$246
2019
$856
2018
$858
Payments by company (2024)
Consulting
Speaking
Meals & Travel
Research
ABBVIE INC.
$38
Top 3 companies account for 100.0% of 2024 payments
All-time payments by company (2018-2024) ›
Amgen Inc.
$468
Novartis Pharmaceuticals Corporation
$366
Celgene Corporation
$205
ABBVIE INC.
$203
PFIZER INC.
$202
AbbVie, Inc.
$180
Lilly USA, LLC
$148
Genentech USA, Inc.
$130
Horizon Therapeutics plc
$75
Janssen Biotech, Inc.
$66
E.R. Squibb & Sons, L.L.C.
$63
Horizon Pharma plc
$40
Prometheus Laboratories Inc.
$35
AbbVie Inc.
$24
DePuy Synthes Sales Inc.
$23
GENZYME CORPORATION
$21
MEDAC PHARMA, INC.
$17
GlaxoSmithKline, LLC.
$14
Top 3 companies account for 45.6% of all-time payments
Associated products mentioned in payments ›
AVSOLA · BENLYSTA · COSENTYX · EVENITY · Enbrel · FORTEO · Humira · KEVZARA · KRYSTEXXA · MONOVISC · ORENCIA · Otezla · Prolia · RAYOS · RINVOQ · Rasuvo · Rinvoq · Rituxan · SIMPONI ARIA · SKYRIZI · STELARA · TALTZ · XELJANZ · Xolair
Should you be concerned? Payments from pharmaceutical and device companies are legal and common — 57% of U.S. physicians receive at least one. They often reflect legitimate consulting, research, or education. What matters is whether a recommended drug or device appears in your doctor's payment records. If so, consider asking your doctor about it. How to interpret this data →
Most payments (100%) are for meals and travel — low-value interactions that are common across virtually all practicing physicians.
Geographic Context
Rheumatologists within 10 mi
204
Per 100K population
2.1
County median income
$87,760
Nearest hospital
CEDARS-SINAI MEDICAL CENTER
0.0 mi
0.0 mi
Data Sources
| Provider Registry | ✓ NPPES | Weekly updates |
| Medicare Enrollment | ✓ PECOS | Monthly updates |
| Practice Data | ✓ Medicare Util. | Annual (CY lag) |
| Industry Payments | ✓ Open Payments | CY 2024 |
| Disciplinary History | — Not public | N/A |
This provider has data in 4 of 4 available federal datasets, with a Data Coverage level of Very High. This reflects how much public data is available about a provider. How we calculate this →
Summary
Dr. Horizon is a mixed practice specialist, with above-average Medicare volume (top 1% in CA), with low-engagement industry engagement, with 20 years of NPI registration.
This summary is auto-generated from federal data, describing data availability and patterns. Read our methodology →
Frequently Asked Questions
Is Dr. Horizon experienced with certolizumab injection (cimzia)?
Based on Medicare claims data, Dr. Horizon performed 138,000 certolizumab injection (cimzia) services. Research suggests that higher procedure volume is often associated with better outcomes, particularly for complex procedures. Note that Medicare data only captures patients aged 65 and older, so the total practice volume across all patients is likely higher.
Does Dr. Horizon receive payments from pharmaceutical companies?
Yes. Dr. Horizon received a total of $2,279 from 18 companies across 106 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common among physicians — 57% of all U.S. physicians receive at least one industry payment. Patients may wish to ask their doctor about these relationships, especially if a recommended drug or device appears in the payment records.
How do Dr. Horizon's costs compare to other rheumatologists in Los Angeles?
Dr. Horizon's average Medicare payment per service is $11. Note that these figures represent what Medicare pays, not your out-of-pocket cost, which depends on your specific insurance plan and deductible. Procedure-level data above shows both what was submitted and what Medicare paid for each service type.
What does Data Coverage mean?
Data Coverage (currently Very High for Dr. Horizon) measures how much public federal data is available about a provider. It is not a quality rating. A "Very High" or "High" level means the provider has data across multiple federal sources (NPPES, PECOS, Medicare Utilization, Open Payments), indicating a long track record of practice, Medicare participation, and industry disclosure. A "Low" or "Moderate" level may simply mean the provider is newer, does not see Medicare patients, or has not received any industry payments — none of which are inherently negative. Read our full methodology →
Is this data up to date?
Each data source has its own update cycle. Provider registry data (NPPES) is updated weekly. Medicare enrollment (PECOS) is updated monthly. Medicare practice data has a ~2 year lag — the most recent available is typically 2 years prior. Industry payment data (Open Payments) is published annually, usually in June, covering the prior calendar year. We display the data date prominently on each section so you always know how current it is. See our data freshness policy →
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About this page
All data on this page is sourced verbatim from public federal records published by the U.S. Centers for Medicare & Medicaid Services (CMS): NPPES ↗, Open Payments ↗, Medicare Provider Utilization ↗, and PECOS. Publication is mandated by the Physician Payments Sunshine Act (§6002 ACA, 42 U.S.C. §1320a-7h) and the Freedom of Information Act.
This page is not medical advice, an endorsement, a recommendation, or a quality rating. Data Coverage reflects data completeness — how much federal information exists for this provider — not clinical performance, patient outcomes, or quality of care. Always verify information directly with the provider and consult a licensed clinician before making medical decisions.
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