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License & Identifications

A medical license is required for a doctor to practice medicine in a particular state. Requirements vary by state but most require, at a minimum, post-graduate training in the doctor’s specific specialty. An NPI number is a national identifier unique to an individual health care provider and is managed by the Center for Medicare & Medicaid Services (CMS).

Patient Reviews

Patient comments (0)

The overall average patient rating of Dr. Dennis Ahnen, Professor is Excellent. Dr. Ahnen has been reviewed by 4 patients who have provided 0 comments. The rating is 5 out of 5 stars.

Patient Ratings
Ease of Appointment 5.0
Promptness 5.0
Courteous Staff 5.0
Accurate Diagnosis 5.0
Bedside Manner 5.0
Spends Time with Me 5.0
Follows Up After Visit 5.0

Specialties & Research

Dr. Dennis Ahnen, MD is board certified in Internal Medicine and Gastroenterology.

  • He has special expertise in 11 areas:
  • Acid Reflux Disease (Gastroesophageal Reflux / GERD)
  • Colon Cancer
  • Colonic Polyps
  • Colonoscopy
  • Colorectal Cancer
  • Constipation
  • Hepatitis C
  • Irritable Bowel Syndrome (IBS)
  • Sigmoidoscopy
  • Tumor Surpressor Gene (Adenomatous Polyposis Coli
  • Ulcerative Colitis

Education & Awards

Dr. Ahnen graduated from Wayne State University, Detroit. He has 5 awards.

One of America's Leading Experts on:
Colon Cancer (Colonic Neoplasm)
Colonic Polyps
Colorectal Cancer (Colorectal Neoplasm)
Castle Connolly's Top Doctors™ (2013)


Dr. Ahnen has 6 hospital affiliations:

  • University Hospital - Denver 
  • Denver Health Medical Center 


  • English

> > > > Dr. Dennis Ahnen, MD

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Additional Information
Dr. Dennis Ahnen MD is a male Internist, has 38 years of experience and practices in Internal Medicine and Gastroenterology.
Where does Dr. Dennis Ahnen practice?
Dr. Dennis Ahnen has 6 office locations.
Dr. Dennis Ahnen practices Internal Medicine and Gastroenterology near Denver, CO.
Additional practice locations include: Golden, CO and Broomfield, CO.
See Denver Internists and Denver Gastroenterologists.