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The overall average patient rating of Dr. Mark O'Hollaren is Excellent.
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Specialties & Research
Dr. Mark O'Hollaren, MD is board certified in Allergy & Immunology and Internal Medicine.
- He has special expertise in 3 areas:
- Hay Fever (Seasonal Allergic Rhinitis)
- Nasal Allergy (Rhinitis)
Education & Awards
Dr. O'Hollaren graduated from Oregon Health & Science University, Portland.
Dr. O'Hollaren has 3 hospital affiliations:
- Providence St Vincent Medical Center
- Oregon Health & Science Univ H, Portland, Or
- Oregon Health Science University
Similar doctors nearby
- Additional Information
- Dr. Mark Thomas O'Hollaren MD is a male Allergist & Immunologist, has 31 years of experience and practices in Allergy & Immunology and Internal Medicine.
- Where does Dr. Mark T. O'Hollaren practice?
- Dr. Mark O'Hollaren has 1 office location.
Dr. Mark O'Hollaren practices Allergy & Immunology and Internal Medicine near Portland, OR.
See Portland Allergists and Portland Internists.