Mount Nittany Physician Group

Specialties and Biography

“Being available to my patients and their families is at the core of my practice,” says Dr. Ruff. “Walking them through the journey from illness to living a healthier life inspires me as a healthcare provider.”

Dr. Ruff earned his bachelor’s degree in biology, with a minor in French, from the University of Utah in Salt Lake City. As an undergraduate student, he volunteered for two years in France and Belgium. Dr. Ruff earned his medical degree from the Penn State College of Medicine in Hershey, Pennsylvania. During this time, he was named a distinguished graduate in Officer Training School at Gunter Air Force Base in Montgomery, Alabama. He also earned the Irwin L. Baird Memorial Award for Outstanding Academic Achievement from the College of Medicine.

Dr. Ruff completed his internal medicine internship and residency at David Grant Medical Center on Travis Air Force Base in Fairfield, California, and his pulmonary/critical care/sleep medicine fellowship at Naval Medical Center in San Diego.

He is a diplomate of the National Board of Medical Examiners; American Board of Internal Medicine. American Board of Internal Medicine, Pulmonary Medicine; American Board of Internal Medicine, Critical Care Medicine; American Board of Internal Medicine, Sleep Medicine; and American Board of Sleep Medicine.

“As a Penn State graduate, I’m thrilled to be back in the area, back to where it all started,” says Dr. Ruff.

Outside of the office, Dr. Ruff enjoys spending time with his wife and their four children, and getting in a round of golf when he can.


Board Certification

American Board of Internal Medicine, American Board of Internal Medicine - Critical Care Medicine, American Board of Internal Medicine - Pulmonary Medicine, American Board of Internal Medicine - Sleep Medicine

Medical Education

The Pennsylvania State University College of Medicine


David Grant Medical Center, Travis AFB


Wellness Articles

by Gregory Ruff, MD

See more

Reviews and ratings

Rating Summary

Provider explanations of prob/condition
4.6 out of 5
75 ratings
Time CP spent with patient
4.6 out of 5
76 ratings
Likelihood of recommending CP
4.6 out of 5
75 ratings
Ease of scheduling appointment
4.6 out of 5
73 ratings


December 27, 2022
Good Experience This was for a second opinion.
December 21, 2022
All good
November 16, 2022
Didn't even get out his stethoscope and he's a pulmonary doctor. Completely unacceptable
November 01, 2022
I have never had a doctor with such poor people skills. Also, it seems that none of my previous doctors were treating me correctly according to Dr. Ruff. I only know the care I received in the past resolved my issues. When I asked Dr. Ruff if I had an issue and needed to be seen, would his office be able to get me in in a timely manner to figure out the issue. Probably not. I will find a different provider for my pulmonary care.
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