Doctor profile · Federal record

Dr. Ronald Markos, MD

Gastroenterology Physician (CMS: Gastroenterology) · Sellersville, PA

  • NPI 1851399786
  • Accepts Medicare
  • 38 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
817 Lawn Ave
Sellersville, PA 189601549
(215) 257-5071
fax (215) 257-1801

Credentials & registration

NPPES · NUCC
NPI registered
July 2005 — 21 yrs on file
Profile last updated
April 27, 2012
Year of graduation
1988 — 38 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State license (1)
Pennsylvania #MD041987L

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1851399786. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,923
Distinct HCPCS
10
Medicare allowed
$284,933
HCPCS Description Services Patients Avg allowed
99213 Established patient office or other outpatient visit, 20-29 minutes 381 331 $91
45385 Removal of polyps or growths of large bowel using an endoscope with mechanical snare 246 244 $259
99214 Established patient office or other outpatient visit, 30-39 minutes 176 162 $129
43239 Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 169 155 $122
46221 Removal of external hemorrhoids by rubber banding 127 68 $302
G0105 Colorectal cancer screening; colonoscopy on individual at high risk 122 122 $186
99203 New patient office or other outpatient visit, 30-44 minutes 117 117 $115
99204 New patient office or other outpatient visit, 45-59 minutes 100 100 $172
99232 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 86 47 $81
43235 Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope 84 80 $102

In context: peer comparison

Among 6 peers in Sellersville Gastroenterology Physician, average services per provider: 73. This provider delivers 26× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$714
Transactions
38
Manufacturers
14
Payer (manufacturer) Industry Txns Amount
Abbvie INC. 20 $371.98
Celgene Corporation 3 $53.23
Phathom Pharmaceuticals, INC. 3 $50.95
Takeda Pharmaceuticals U.S.A., INC. 2 $36.02
Janssen Biotech, INC. 1 $31.40
Lilly USA, LLC 1 $21.95
Salix Pharmaceuticals, A Division of Bausch Health US, LLC 1 $21.62
Ironwood Pharmaceuticals, INC 1 $21.28
Celltrion USA INC. 1 $21.27
Boehringer Ingelheim Pharmaceuticals, INC. 1 $19.70
Genzyme Corporation 1 $19.27
CapsoVision, INC. 1 $18.24
Gilead Sciences, INC. 1 $15.49
Endogastric Solutions, INC 1 $11.58

By nature of payment

Food and Beverage
$714

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
1,731
Patients
445
Total drug cost
$329,684
Drug Type Claims Patients Total cost
Famotidine Generic 767 225 $17,532
Omeprazole Generic 454 115 $3,915
Pantoprazole Sodium Generic 191 49 $5,791
Mesalamine Generic 56 11 $33,298
Colestipol Hcl Generic 38 11 $3,780
Dicyclomine Hcl Generic 30 14 $820
Humira(Cf) Pen (Adalimumab) Brand 27 0 $208,959
Spironolactone Generic 25 0 $392
Gavilyte-G (Peg3350/Sod Sulf,Bicarb,Cl/Kcl) Brand 23 20 $401
Vemlidy (Tenofovir Alafenamide) Brand 23 0 $37,106

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Ronald Markos's medical specialty?
Dr. Ronald Markos practices Gastroenterology Physician in Sellersville, PA.
Where does Dr. Ronald Markos practice?
Dr. Ronald Markos practices at 817 Lawn Ave, Sellersville, PA 189601549. Office phone: 2152575071.
What is Dr. Ronald Markos's NPI?
Dr. Ronald Markos's National Provider Identifier (NPI) is 1851399786, issued by NPPES.
Does Dr. Ronald Markos accept Medicare assignment?
Yes. Dr. Ronald Markos accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Ronald Markos commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99213); Removal of polyps or growths of large bowel using an endoscope with mechanical snare (HCPCS 45385); Established patient office or other outpatient visit (HCPCS 99214). Source: CMS Medicare Physician & Other Practitioners file.