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Dr. Mark Thomas O'Hollaren, MD

  • Portland, OR
  • Allergy physician
NPI1588723787
Publications
8
Affiliated sites
1
Medical group
1
State licenses
4
Year NPI issued
2006
Practice address
511 Sw 10th Ave, Portland, OR 97205-2732
Practice phone
Call (503) 228-0155
Professional email
Get professional email
Personal email
Get personal email
Mobile number
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Social profiles

Primary practice

Allergy Clinic

Medical specialty practice · Portland, Oregon

See all 2 affiliations

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Dr. Mark Thomas O'Hollaren is an allergy physician in Portland, Oregon

Dr. O'Hollaren practices at Allergy Clinic in Portland, Oregon.

Dr. O'Hollaren's NPI, 1588723787, was assigned on December 6, 2006. Dr. O'Hollaren graduated from OHSU School of Medicine in 1980. Dr. O'Hollaren's Oregon license number on file is 13450.

NPI and contact details
NPI
1588723787NPI Registry (opens in a new tab)
NPI enumeration date
December 6, 2006
NPI status
Active
Practice phone
(503) 228-0155
Professional email
Get email
Personal email
Get email
Mobile number
Get number
Medical school graduation
1980

Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)

Dr. Mark Thomas O'Hollaren practices at Allergy Clinic in Portland, Oregon

Dr. O'Hollaren's primary practice is Allergy Clinic, at 511 Sw 10th Ave, Portland, OR 97205-2732. The practice phone is (503) 228-0155.

  • Allergy Clinic
    511 Sw 10th Ave, Portland, OR 97205-2732Phone(503) 228-0155

Sources: Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)

Dr. Mark Thomas O'Hollaren is affiliated with 1 site of care and 1 medical group

Dr. O'Hollaren's primary practice is Allergy Clinic in Portland, Oregon. Dmand AI also links Dr. O'Hollaren to 1 medical group, named with a free account.

Allergy ClinicMedical specialty practice · Portland, OregonPrimary
1 medical groupName with a free account
See all 2 affiliations for Dr. O'Hollaren

Sources: Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)

Dmand AI tracks the EHR system at Dr. Mark Thomas O'Hollaren's practice

Dmand AI tracks the electronic health record (EHR) system at each site where Dr. O'Hollaren practices. Vendor and product names are available with a free account.

EHR by site
SiteEHR vendor and product
Allergy ClinicAvailable with a free account
+1 medical groupAvailable with a free account

Source: Dmand AI Technology Install Data

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Dr. Mark Thomas O'Hollaren is one of 7 allergy physicians in Oregon

Allergy is Dr. O'Hollaren's primary specialty in the NPI Registry, under taxonomy code 207KA0200X. Dr. O'Hollaren is board certified in allergy & immunology by the American Board of Allergy and Immunology. Dmand AI has Dr. O'Hollaren's licenses on file in 4 states: Oregon, Washington, Minnesota and Wisconsin.

Specialties and state licenses

  • Allergy, OregonPrimaryLicense 13450 · 1983 to 2025 · taxonomy 207KA0200X
  • Washington license1986 to 2008
  • Minnesota license1984 to 1987
  • Wisconsin license1984 to 1985

Allergy physicians near Dr. O'Hollaren

Counts of allergy physicians with a Dmand AI profile, by place and practice. Each opens the list.

7allergy physicians in Oregon
4allergy physicians in Portland

Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks

Dr. Mark Thomas O'Hollaren has 8 publications on record

Dmand AI links 8 papers to Dr. O'Hollaren in 2007. The most frequent topics are Asthma, Air Pollutants, Occupational and Allergens. Dr. O'Hollaren has published most often in Chest. Dr. O'Hollaren's most frequent co-authors are David Ballard, DDS and Michael J. Somers, MD.

Papers8

Topics Dr. O'Hollaren writes about most

  • Asthma
  • Air Pollutants, Occupational
  • Allergens
  • Health Maintenance Organizations
  • Occupational Diseases
  • Predictive Value of Tests

Dr. O'Hollaren's most frequent co-authors

Recent publications by Dr. O'Hollaren

See all 8 publications and co-authors

See who Dr. O'Hollaren researches with

Physician Network Discovery turns co-authorship, shared hospitals and shared groups into a map of who Dr. O'Hollaren works with, so you can find a warm path to the right allergy physicians.

How network discovery works

Sources: PubMed (National Library of Medicine); and Dmand AI Research Linkage

Dr. Mark Thomas O'Hollaren has 1 award and honors on record

Dmand AI lists 1 award for Dr. O'Hollaren.

Awards and honors for Dr. O'Hollaren

  1. Undated
    • Checkbook Top Doc

Source: Dmand AI Professional Profile Data

Dr. Mark Thomas O'Hollaren graduated from OHSU School of Medicine

Dr. O'Hollaren graduated from OHSU School of Medicine in 1980.

  1. Medical schoolOHSU School of Medicine
  2. Board certified in allergy & immunologyAmerican Board of Allergy and Immunology
  3. Board certified in internal medicineAmerican Board of Internal Medicine

Source: Dmand AI Professional Profile Data

Sources for Dr. Mark Thomas O'Hollaren's profile data

Sources for the data on this page
Data on this pageSource
NPI, name, sex, specialty and licensesNPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data
Practice locations and phoneDmand AI Affiliation DataDoctors and Clinicians National Downloadable File (CMS) (opens in a new tab)
Primary practice, affiliations and health systemDmand AI Affiliation DataDoctors and Clinicians National Downloadable File (CMS) (opens in a new tab)
Publications, topics and co-authorsPubMed (National Library of Medicine) (opens in a new tab)Dmand AI Research Linkage
Awards and committee rolesDmand AI Professional Profile Data
Training, board certification and membershipsDmand AI Professional Profile Data
EHR at each practice siteDmand AI Technology Install Data
Similar physiciansDmand AI Affiliation Data

Data last refreshed October 2026Report an inaccuracyRemove my information

FAQ

Frequently asked questions about Dr. Mark Thomas O'Hollaren

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 Thomas O'Hollaren's NPI number?

Dr. Mark Thomas O'Hollaren's NPI number is 1588723787. It was assigned on December 6, 2006, and it is active in the NPI Registry.

What kind of doctor is Dr. Mark Thomas O'Hollaren?

Dr. Mark Thomas O'Hollaren is an allergy physician in Portland, Oregon. The primary specialty in the NPI Registry is Allergy Physician (taxonomy code 207KA0200X).

Where does Dr. Mark Thomas O'Hollaren practice?

Dr. O'Hollaren practices at 511 Sw 10th Ave, Portland, OR 97205-2732. Dr. O'Hollaren's primary practice is Allergy Clinic in Portland, Oregon. Dmand AI also links Dr. O'Hollaren to 1 medical group.

What is Dr. Mark Thomas O'Hollaren's office phone number?

The practice phone on file for Dr. O'Hollaren is (503) 228-0155.

What is Dr. Mark Thomas O'Hollaren's medical license number?

Dr. O'Hollaren's Oregon license number on file is 13450, one of the licenses on file in 4 states.

Which states has Dr. Mark Thomas O'Hollaren been licensed in?

Dmand AI has state licenses on file for Dr. O'Hollaren in Oregon (1983 to 2025), Washington (1986 to 2008), Minnesota (1984 to 1987) and Wisconsin (1984 to 1985).

Is Dr. Mark Thomas O'Hollaren board certified?

Yes. Dr. O'Hollaren is board certified in allergy & immunology by the American Board of Allergy and Immunology.

Where did Dr. Mark Thomas O'Hollaren go to medical school?

Dr. O'Hollaren graduated from OHSU School of Medicine in 1980.

How long has Dr. Mark Thomas O'Hollaren been practicing?

Dr. O'Hollaren graduated from medical school in 1980, 46 years ago.

Does Dr. Mark Thomas O'Hollaren do research?

Dmand AI links 8 publications to Dr. O'Hollaren.

Who does Dr. Mark Thomas O'Hollaren publish with?

Dr. O'Hollaren's most frequent co-authors are David Ballard, DDS (1 shared paper) and Michael J. Somers, MD (1 shared paper).

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