Dr. Mark A. Isaeff, MD
- Medicare services, 2024
- 403
- Medicare patients, 2024
- 158
- Part D claims, 2024
- 2,918
- Industry payments
- $1,524
- Affiliated sites
- 1
- Practice address
- 1303 McCullough Ave, San Antonio, TX 78212
- Practice phone
- Call (210) 226-8349
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Rafael Parra and Associates MD PA
San Antonio, Texas
Find Dr. Isaeff's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Dr. Mark A. Isaeff is an internist in San Antonio, Texas
Dr. Isaeff practices at Rafael Parra and Associates MD PA in San Antonio, Texas.
Dr. Isaeff's NPI, 1104815075, was assigned on October 13, 2005. Dr. Isaeff graduated from Georgetown University School Of Medicine in 1998. Dr. Isaeff holds Texas license K8638.
- NPI
- 1104815075NPI Registry (opens in a new tab)
- Medicare PAC ID
- 1951437805
- NPI enumeration date
- October 13, 2005
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (210) 226-8349
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 54
- Medical school graduation
- 1998
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Practice Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Mark A. Isaeff practices at Rafael Parra and Associates MD PA in San Antonio, Texas
Dr. Isaeff's primary practice is Rafael Parra and Associates MD PA, at 1303 McCullough Ave, San Antonio, TX 78212 in Bexar County. The practice phone is (210) 226-8349.
- Rafael Parra and Associates MD PA1303 McCullough Ave, San Antonio, TX 78212 · Bexar CountyPhone(210) 226-8349
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Dr. Mark A. Isaeff is affiliated with 2 sites of care
Dr. Isaeff's primary practice is Rafael Parra and Associates MD PA in San Antonio, Texas. Dmand AI also links Dr. Isaeff to 1 physician office, named with a free account.
Sources: NPPES NPI Registry (CMS); Dmand AI Practice Data; and Dmand AI Affiliation Data
Dmand AI tracks the EHR system at Dr. Mark A. Isaeff's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Isaeff practices. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Rafael Parra and Associates MD PA | Available with a free account |
| +1 more affiliated site | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Mark A. Isaeff is one of 8,437 internists in Texas
Internal medicine is Dr. Isaeff's primary specialty in the NPI Registry, under taxonomy code 207R00000X. Dr. Isaeff is licensed in Texas.
Specialties and state licenses
- Internal medicine, TexasPrimary
Clinical focus
Dmand AI lists acute gastroduodenitis, acute sinusitis, acute skin infection, aneurysm, atrial fibrillation and flutter, bronchitis, chronic hypertension and conjunctivitis among the conditions Dr. Isaeff treats.
Internists near Dr. Isaeff
Counts of internists with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. Mark A. Isaeff billed Medicare for 403 services in 2024
CMS data shows 403 Medicare services from Dr. Isaeff across 1 procedure code in 2024, all of them office visits, for 158 Medicare patients. Medicare paid $32,526 for them. Every service was in an office.
Dr. Isaeff's Medicare services by type, 2023 to 2024
- 2023
- 2024
- Office and hospital visits
- 2023: 4702024: 40314%
Dr. Isaeff compared with the Texas median for internists, 2024
- Dr. Isaeff
- Texas median
- Medicare services
- 403vs 53925% below
- Medicare patients
- 158vs 19017% below
- Part D claims
- 2,445vs 2898.5 times
Medians across 7,794 internists in Texas with Dmand AI profiles that report each measure.
Dr. Isaeff's most billed Medicare procedure codes, 2024
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
Need commercial claims for Dr. Isaeff?
Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Isaeff and other internists in Texas.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Mark A. Isaeff treated 158 Medicare patients in 2024, average age 78
CMS counts 158 Medicare patients who saw Dr. Isaeff in 2024. The largest group is 75 to 84, with 66 patients. 75% of them have high blood pressure, and 75% have high cholesterol. Their average risk score is 1.02, where 1.00 is the Medicare average.
Across all payers, Dmand AI patient panel data puts Dr. Isaeff's median patient age at 74, with 54% women.
Dr. Isaeff's Medicare patients by age, 2024
CMS leaves out age groups with fewer than 11 patients.
Dr. Isaeff's Medicare patients by sex, 2024
- Women8554%
- Men7346%
Chronic conditions among Dr. Isaeff's Medicare patients, 2024
- High blood pressure75%
- High cholesterol75%
- Ischemic heart disease75%
- Arthritis36%
- Diabetes28%
- Atrial fibrillation24%
- Mood disorders22%
- Depression20%
Share of Medicare patients with each condition. A patient can have several.
Dr. Isaeff's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 74
Patient panel by sex, all payers
- Women54%
- Men43%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2024 data
Dr. Mark A. Isaeff wrote 2,918 Medicare Part D claims in 2024
In 2024, Dr. Isaeff wrote 2,918 Medicare Part D claims for 181 patients. 87% of them were for generic drugs. CMS names the drug for 2,445 of them, across 49 drugs with 11 or more claims each, at $212,867 in total drug cost. In 2023, CMS named 3,014 claims across 65 drugs.
Dr. Isaeff's Part D claims by kind of drug, 2024
- Generic2,532 claims87%
- Brand-name and other386 claims13%
Dr. Isaeff's most prescribed drugs by claims, 2024
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Drug classes CMS tracks in Dr. Isaeff's Part D claims, 2024
- Opioids0%11 of 2,918 claims
- Antibiotics7%203 of 2,918 claims
Share of all Part D claims for each drug class CMS reports on. Classes with no claims are left out.
Part D claims for drugs CMS names, 2023 to 2024
- 2023
- 2024
- Claims for drugs CMS names
- 2023: 3,0142024: 2,44519%
Drugs named by CMS: 49 in 2024, 65 in 2023.
Sources: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026; and Medicare Part D Prescribers - by Provider (CMS), 2024 data
How Dr. Mark A. Isaeff takes part in Medicare
Dr. Isaeff accepts Medicare assignment, so Medicare's approved amount is taken as full payment.
- Accepts Medicare assignment
- Yes
Source: Doctors and Clinicians National Downloadable File (CMS)
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Dr. Mark A. Isaeff received $1,524 in industry payments from 2016 to 2025
CMS Open Payments shows 111 general payments to Dr. Isaeff from 21 drug and device companies from 2016 to 2025. Food and beverage make up the largest share, 99% of the total. Amarin Pharma Inc. paid the most, $451.
General payments to Dr. Isaeff by program year, 2016 to 2025
General payments to Dr. Isaeff by kind, 2016 to 2025
- Food and beverage$1,50499%
- Education$201%
Companies that paid Dr. Isaeff the most, 2016 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Mark A. Isaeff graduated from Georgetown University School Of Medicine
Dr. Isaeff graduated from Georgetown University School Of Medicine in 1998.
- Medical school
Source: Dmand AI Professional Profile Data
Dr. Mark A. Isaeff accepts plans from 13 insurance carriers
Dr. Isaeff is in network with 13 carriers, including Aetna, Elevance and United Healthcare. PPO plans come from the most carriers, 8. Check the plan with the practice before a visit.
- Aetna
- Elevance
- United Healthcare
- Blue Cross Blue Shield of Michigan
- Aspirus Health Plan
- HCSC
- Humana
- Alliant Health Plans
- +5 more carriersWith a free account
Plan types Dr. Isaeff accepts, by number of carriers
- PPO8
- HMO7
- POS5
- EPO4
- Medicare4
Source: Dmand AI Insurance Network Data
Sources for Dr. Mark A. Isaeff's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Primary practice, affiliations and health system | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice DataDmand AI Affiliation Data |
| Medicare services and procedure codes | Medicare Physician & Other Practitioners - by Provider and Service (CMS) (opens in a new tab) |
| State medians for the same specialty | Dmand AI Peer Benchmarks |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab)Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| Insurance carriers and plan types | Dmand AI Insurance Network Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. Mark A. Isaeff
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. Mark A. Isaeff's NPI number?
Dr. Mark A. Isaeff's NPI number is 1104815075. It was assigned on October 13, 2005, and it is active in the NPI Registry.
What kind of doctor is Dr. Mark A. Isaeff?
Dr. Mark A. Isaeff is an internist in San Antonio, Texas. The primary specialty in the NPI Registry is Internal Medicine Physician (taxonomy code 207R00000X).
Where does Dr. Mark A. Isaeff practice?
Dr. Isaeff practices at 1303 McCullough Ave, San Antonio, TX 78212. Dr. Isaeff's primary practice is Rafael Parra and Associates MD PA in San Antonio, Texas. Dmand AI also links Dr. Isaeff to 1 physician office.
What is Dr. Mark A. Isaeff's office phone number?
The practice phone on file for Dr. Isaeff is (210) 226-8349.
What is Dr. Mark A. Isaeff's medical license number?
Dr. Isaeff holds Texas license K8638.
Does Dr. Mark A. Isaeff accept Medicare?
Yes. CMS data shows Dr. Isaeff billed Medicare for 403 services in 2024, and Dr. Isaeff accepts Medicare assignment.
How many Medicare patients does Dr. Mark A. Isaeff see?
CMS counts 158 Medicare patients who saw Dr. Isaeff in 2024, with an average age of 78.
What services does Dr. Mark A. Isaeff bill to Medicare?
In 2024, Dr. Isaeff's most billed Medicare services were office visit, established patient (99214).
Where did Dr. Mark A. Isaeff go to medical school?
Dr. Isaeff graduated from Georgetown University School Of Medicine in 1998.
What drugs does Dr. Mark A. Isaeff prescribe most?
In 2024 Medicare Part D data, Dr. Isaeff's most prescribed drugs by claims were Rosuvastatin Calcium, Losartan Potassium and Carvedilol.
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Has Dr. Mark A. Isaeff received payments from drug or device companies?
CMS Open Payments shows $1,524 in general payments to Dr. Isaeff from 21 companies from 2016 to 2025. The largest total came from Amarin Pharma Inc.
How long has Dr. Mark A. Isaeff been practicing?
Dr. Isaeff graduated from medical school in 1998, 28 years ago.
What insurance does Dr. Mark A. Isaeff accept?
Dr. Isaeff is in network with 13 carriers, including Aetna, Elevance and United Healthcare. PPO plans come from the most carriers, 8. Check the plan with the practice before a visit.
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