MAGHA DISSANAYAKE, MD
Internal Medicine Physician in SPRINGFIELD, Oregon. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.
What the federal data shows
MAGHA DISSANAYAKE, MD filed 4,507 Medicare Part D claims in 2023 as a Internal Medicine Physician in SPRINGFIELD, Oregon, prescribing 91% generic.
- 5K
- Part D claims, 2023
- 91%
- generic prescribing
- Likely
- board-certified (heuristic)
Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) — no proprietary rating or editorial opinion is applied.
MAGHA DISSANAYAKE, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023 — across all CMS prescribers nationally
4,507 Top 7% higher than 93% of 1,370,886 prescribers
Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source CMS Medicare Part D Prescriber Public Use File · 2023
MAGHA DISSANAYAKE, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about MAGHA DISSANAYAKE, MD?
Quality data not reportedPrimary specialty
Medicare Part D claims
Specialty distribution in Oregon
How Internal Medicine Physician compares to other specialties among Oregon providers
Internal Medicine Physician share within Oregon
Internal Medicine Physician is one of the more visible NUCC categories in Oregon
Each bar reflects the share of in-state providers whose primary NUCC taxonomy matches the specialty. Long tail of ~690 NUCC codes folded into "Other" to keep the comparison legible.
Specialty board-certification context
Estimated specialty board-certified rate — Internal Medicine Physician (ABMS / AOA reference)
- Est. board-certified rate
- 78%
- Internal Medicine Physician ABMS/AOA estimate
Est. board-certified rate (Internal Medicine Physician) — ABMS / AOA estimate
Verify credentials
- Verify via ABMS free public lookup
- Verify via AOA osteopathic boards
- Specialty volume Internal Medicine Physician US NPIs
Specialty board-certified rate — Internal Medicine Physician estimate
Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus Maintenance of Certification cycles. CMS does not publish a per-provider board-certification field; the figure shown is the specialty-level estimated rate from ABMS / AOA reference data.
The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.
Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).
MAGHA DISSANAYAKE, MD appears in the CMS NPPES registry as a Internal Medicine Physician provider holding MD credentials at 147 S 52ND PL, SPRINGFIELD, OR, 97478, with a listed phone of (541) 746-1166. NPI 1578545182 was issued on 11/18/2005. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what DISSANAYAKE most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.
Medicare Part D records for calendar year 2023 show 4,507 prescription claims written by this provider, covering 795 Medicare beneficiaries and totaling roughly $343K in drug spend, split 9% brand-name and 91% generic by claim count, with an opioid prescribing rate of 5.0%. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.
Internal Medicine Physician is a high-volume specialty nationwide, with 172,858 enrolled providers across 56 states and an average of 2,716 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.
Practice Address
Provider Details
| NPI | 1578545182 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 11/18/2005 |
Verify this provider's license
PlainDoctor pulls this profile from the CMS NPPES public registry. Confirm MAGHA DISSANAYAKE, MD's current license status, disciplinary history, and board certifications with the Oregon Medical Board in Oregon before relying on this page for a clinical or care decision.
How we sourced this profile
Hospital and facility affiliations
Facilities where MAGHA DISSANAYAKE, MD bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" — a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
Industry payments received (2024) — CMS Open Payments transparency data
The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for MAGHA DISSANAYAKE, MD. Source: openpaymentsdata.cms.gov.
Total received
$988
Largest payer
PFIZER INC.
Most common payment type
Food and Beverage
Industry payments are not necessarily indicators of bias — they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.
Brand vs generic prescribing mix · Generic-heavy
9% brand-name claims vs 91% generic, on 4,507 2023 Medicare Part D claims.
The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.
Medicare Part D Prescribing Data
CMS Medicare Part D prescriber-level data for calendar year 2023.
Prescribing Breakdown
- 30-Day Fills
- 9,083
- Total Day Supply
- 263,290
- Brand vs Generic
- 9% brand / 91% generic
- Brand Drug Cost
- $247K
- Generic Drug Cost
- $94K
- Opioid Claims
- 227 (5.0% rate)
- Antibiotic Claims
- 127
Patient Demographics
- Average Patient Age
- 74.0 years
- Avg HCC Risk Score
- 1.36
- Gender Split
- 56% female / 44% male
- Age Distribution
- <65: 73, 65-74: 353, 75-84: 268, 85+: 101
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What MAGHA DISSANAYAKE, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
219 claims
- Levothyroxine Sodium
Levothyroxine Sodium
212 claims
- Gabapentin
Gabapentin
143 claims
- Lisinopril
Lisinopril
131 claims
- Meloxicam
Meloxicam
108 claims
- Hydrochlorothiazide
Hydrochlorothiazide
106 claims
- Amlodipine Besylate
Amlodipine Besylate
102 claims
- Losartan Potassium
Losartan Potassium
100 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 219 |
| Levothyroxine Sodium | 212 |
| Gabapentin | 143 |
| Lisinopril | 131 |
| Meloxicam | 108 |
| Hydrochlorothiazide | 106 |
| Amlodipine Besylate | 102 |
| Losartan Potassium | 100 |
| Metoprolol Succinate | 99 |
| Tamsulosin Hcl | 93 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Internal Medicine Physician Overview
How MAGHA DISSANAYAKE, MD fits within the Internal Medicine Physician landscape nationally.
MAGHA DISSANAYAKE, MD's 4,507 claims are above the specialty average of 2,716.
Nearby Internal Medicine Physician Providers in Oregon
Other clinicians with the same primary specialty enrolled in Oregon, drawn from the same CMS NPPES roster as DISSANAYAKE.
Compare Internal Medicine Physician nationally: see state-by-state distribution →
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Frequently Asked Questions
What is MAGHA DISSANAYAKE, MD's specialty? ▼
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Does MAGHA DISSANAYAKE, MD prescribe more brand-name or generic drugs? ▼
Does MAGHA DISSANAYAKE, MD prescribe opioids? ▼
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Data Sources
- Provider Directory
- CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
- Specialty Classification
- NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
- Prescribing Data
- CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
- Limitations
- Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.
See our complete data methodology for details on how we collect and process government data.
Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).
Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology