DR. FREDERICK W RUYMANN (MD) – Gastroenterology Physician, NPI 1568466316
Gastroenterology Physician
Main info
Doctor Profile
Profile Insights
NPPES metrics only — not quality of care.
828 GASTROENTEROLOGY in MA
Loading map...
Provider Addresses for DR. FREDERICK W RUYMANN (MD)
300, Mount Auburn Street, Old Cambridge, Cambridge, Middlesex County, Massachusetts, 02138, United States
STE 405
CAMBRIDGE, MA 021385502
Phone: (617) 661-0221
Fax: (617) 661-3862
Mailing address matches the actual address.
NPPES updates history
No NPPES updates recorded for this provider.
Prescription Activity
Loading prescription activity...
Open Payments (CMS)
CMS reports 137 Open Payments records for all available years, with a total value of $3,531.
Total Amount is formed as General ($3,531) + Research ($0) + Ownership ($0) = $3,531.
Last reported payment date: 2024-12-18 • Largest payer in this snapshot: ABBVIE INC. ($970).
Total Amount
$3,531
General + Research + Ownership
Payments
137
Total payment records
General Amount
$3,531
General payments
Research Amount
$0
Research funding
Ownership Amount
$0
Ownership interests
Ownership Count
0
Ownership records
Last Payment Date
2024-12-18
Latest reported date
Top Companies
Largest payers in this snapshot
Medicare Enrollment & Revalidation
Source: CMS public data · Not endorsed by CMS ·
Educational use only—not medical, billing, or legal advice.
PECOS enrollment status
Participating (accepts Medicare assignment)
Enrollment effective: 2005-04-06
PECOS data refreshed: 2026-05-27
Medicare revalidation (CMS due date list)
Due date not assigned yet
CMS is tracking this Medicare enrollment for revalidation, but has not published a due date.
Enrollment records
1
Earliest due date
Not assigned (TBD)
CMS data updated
2026-06-01
Revalidation progress
- Medicare enrolled
- On CMS revalidation list
- Due date assigned
- Revalidate in PECOS
CMS enrollment records
| Enrollment ID | Type | Specialty | State | Due date |
|---|---|---|---|---|
| I20050406000259 | I | Gastroenterology | MA | TBD |
What to do next
- No action required while the due date shows TBD.
- Check the CMS Revalidation Lookup Tool periodically — CMS updates the list about every 60 days.
- Do not submit a revalidation application in PECOS until CMS publishes a concrete due date.
Prepare CMS-855 application → · Look up this NPI in PECOS → · Verify on CMS PECOS
Medicare Utilization (FFS)
Source: CMS public data · Not endorsed by CMS · Beneficiary counts under 11 are suppressed in source data ·
Educational use only—not medical, billing, or legal advice.
Top Medicare procedures (2023) · refreshed 2026-05-27
| HCPCS | Description | Services | Beneficiaries | Medicare allowed |
|---|---|---|---|---|
| 99213 | Established patient office or other outpatient visit, 20-29 minutes | 267 | 190 | $0 |
| 43235 | Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope | 128 | 122 | $0 |
| 43239 | Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope | 123 | 121 | $0 |
| 45378 | Diagnostic exam of large bowel using a flexible endoscope | 73 | 72 | $0 |
| 43264 | Removal of stone or debris from bile or pancreatic duct using a flexible endoscope | 72 | 69 | $0 |
Insurance plans in this area (ZIP 02138)
Loading plans...
Provider's Procedures
Group practice members
| Name | Specialty | State |
|---|---|---|
| E N D O C R I N O L O G Y | MA | |
| Nurse Practitioner | MA | |
| Physician Assistant | MA | |
| Internal Medicine, Cardiovascular Disease (Cardiology) | MA | |
| Family Practice | MA | |
| Internal Medicine | MA | |
| Thoracic Surgery, General Surgery | MA | |
| - | MA | |
| N E U R O S U R G E R Y | MA | |
| - | NV |
Reviews
All reviews are moderated before publication. Reviews reflect users' opinions; we do not verify the accuracy of individual reviews.
No reviews yet. Be the first to share your experience — your opinion helps families compare providers.