William C. Bayer, MD

William C. Bayer, MD

4.9 
1738 ratings  Read Reviews
Northwestern Medicine logoNorthwestern Medicine Regional Medical Group

Primary Specialty

Endocrinology

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Education

Medical Education:
MD, Loyola University Stritch School of Medicine - 1986
Residency:
Loyola University Medical Center - 1989
Fellowships:
Loyola University Medical Center - 1991

Board Certifications

  • American Board of Internal Medicine - Endocrinology, Diabetes & Metabolism (Certified)
  • American Board of Internal Medicine - Internal Medicine (Certified)

Practice Groups and Affiliations

Medical Group:
Northwestern Medicine Regional Medical Group
Alignment Category:
Northwestern Medicine Physician Network
On Medical Staff At:
Central DuPage Hospital

Ratings and Reviews

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Overall Rating

4.9
4.9 

1738 Ratings

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Reviews from Patients

100 Most Recent Reviews

Reviews from Patients

Sort By Newest
100 Most Recent Reviews

April 29, 2025

5.0

He's easy to talk with, answers questions, isn't an alarmist, allows me to be part of the decision making.

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April 28, 2025

5.0

Dr. Bayer remains caring and an effective listener.

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April 25, 2025

5.0

Caring .Thorough! Thoughtful ! Dr Bayer

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April 24, 2025

5.0

Knowledgeable

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April 22, 2025

5.0

He listens and is always kind and he's super smart

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April 22, 2025

5.0

Knowlegable

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April 21, 2025

5.0

He knows diabetes.

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April 19, 2025

5.0

Awesome bedside manner!

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April 17, 2025

5.0

I would rate him higher than a 10!! I've been his patient for many years. He's not only my Dr but a friend. He's caring and extremely competent.

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April 14, 2025

5.0

Attention to detail and very thorough

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April 11, 2025

4.0

Seem to be a good doctor. Just getting to know him.

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April 09, 2025

5.0

Very knowledgable and encouraging.

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April 08, 2025

5.0

Dr. Bayer is the best

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April 05, 2025

5.0

Dr Bayer was friendly, listened to me, was prepared for our visit and clearly explained what he suggested for possible treatment. I was very impressed with him.

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April 04, 2025

5.0

he is on top of everything - goes over everything and seems to care - very kind and friendly every time you see him.

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April 02, 2025

5.0

He is a outstanding doctor

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April 01, 2025

5.0

Knowledgeable, efficient, friendly

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April 01, 2025

5.0

He is wonderful! Very friendly and I trust his expertise completely. He takes time to listen to my concerns and always has good advice.

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March 22, 2025

5.0

I really enjoy Dr.Bayer. He is kind and insightful. I always get good care.

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March 20, 2025

5.0

He is social and professional doctor

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March 20, 2025

5.0

He's very good

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March 16, 2025

5.0

Dr Bayer is very easy to talk to me

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March 16, 2025

5.0

Explained everything so I could understand.

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March 13, 2025

5.0

He is helpful and answers my questions.

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March 13, 2025

5.0

Dr. Bayer always listens to my concerns and treats me with respect.

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March 10, 2025

5.0

He takes the time to talk to you and explains ant questions. He is very caring.

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March 10, 2025

5.0

Great care, as always! Very knowledgeable and personable

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March 07, 2025

5.0

Great doctor.

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March 04, 2025

5.0

Experience doctor

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March 01, 2025

4.0

Good and knowledgeable

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February 27, 2025

5.0

This MD is excellent with bedside manner, explanation of problems, prognosis and plan of action.

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February 27, 2025

5.0

Great discussion of medical issues

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February 25, 2025

5.0

He has solved my troubles and brought me to a steady, healthy place.

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February 24, 2025

5.0

I have known him for many years. He has always taken good care of me.

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February 23, 2025

5.0

Makes you feel comfortable and is very informative

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February 20, 2025

5.0

The ladies in reception area, staff in back to include Dr. Bayer is always pleasant and the wait time is very minimum. I would highly recommend this office to anyone who has diabetes. Big shoutout to all listed above : GREAT JOB!

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February 19, 2025

5.0

He's extremely knowledgeable in his field. He gave us a lot of answers that we never even knew we had questions for but it was very comforting, knowing that he set us at ease!

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February 18, 2025

5.0

Always impressed with his knowledge and caring attitude.

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February 17, 2025

5.0

He is understanding of my concerns

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February 10, 2025

5.0

Dr. Bayer is always very thorough and takes his time going through everything with me. He is very attentive and treats you like family. I highly recommend him for diabetes patients, and I see him for thyroid issues. He is truly a wonderful Dr. and I would know as I have seen him with my mom for over 25 years now.

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February 07, 2025

5.0

He's awesome!

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February 06, 2025

5.0

Caring

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February 02, 2025

5.0

He is very thorough and listens to his patient. He is an excellent doctor.

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February 01, 2025

5.0

Dr. Bayer cares and listens to his patients. Knowledgeable and friendly.

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January 29, 2025

5.0

Fast, friendly, convenient and personable.

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January 29, 2025

5.0

Fits the program to the individual.

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January 28, 2025

5.0

Top notch doctor, very knowledgeable and caring

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January 27, 2025

5.0

Very knowledgeable

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January 27, 2025

5.0

Very complete review of not only his own information but that of my other NW doctors

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January 23, 2025

5.0

Dr.Bayer always answer all my questions. He is the best.

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January 22, 2025

5.0

Dr. Bayer provided me with great help in controlling my diabetes issues with positive encouragement.

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January 22, 2025

5.0

Really listens and does rush. Thorough and explains he thoughts on treatment plan. Plus prints out details of what was discussed and up coming treatment.

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January 21, 2025

5.0

Great doctor

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January 18, 2025

5.0

Great job

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January 13, 2025

5.0

I have great confidence in Dr. Bayer's professional qualifications as well as his treatment of older patients. My visits are very efficient and Dr. Bayer is always aware of my history and respectful of the treatment decisions I have made. I would be happy to recommend him to anyone.

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January 12, 2025

5.0

He is knowledgeable, kind and has a wonderful sense of humor. And he always takes time to explain things and I always feel better when I leave his office.

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January 08, 2025

5.0

He is friendly, kind and very intelligent! Really knows what he's doing!

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December 31, 2024

5.0

Knowledgeable, considerate and thorough

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December 30, 2024

5.0

Went over care plan & gave me time to ask any followup questions

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December 28, 2024

5.0

Always thinking of the best way to treat me!

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December 23, 2024

5.0

Dr. Bayer is very professional, caring and thorough.

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December 23, 2024

5.0

He is so nice and caring. He takes time to explain things and I feel he really cares about his patients.

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December 15, 2024

5.0

He's the best!

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December 11, 2024

5.0

Explains test results completely. Talks about what's coming up

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December 11, 2024

5.0

Dr. Bayer is thorough and takes excellent care of me.

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December 10, 2024

5.0

Knowledgeable and concerned about all areas of health

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December 10, 2024

5.0

easy to relate to, listens when i have concerns

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December 10, 2024

5.0

Dr, Bayer is my 4th Endocrinologist. He is the only one who knew how to help me. So glad I found him!

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December 07, 2024

5.0

Dr Bayer is thorough in his screening and checks vitaminD levels, bone density, and thyroid levels. He's personable with his patients.

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December 02, 2024

5.0

Dr Bayer was very professional, thorough, good communicator and continuously asked if I had any questions.

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December 02, 2024

5.0

Is an expert in his field and address all issues.

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November 19, 2024

5.0

Dr Bayer is very attentive and provides very good answers to any questions.

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November 19, 2024

5.0

Dr Bayer has been caring & kind & helpful & encouraging, & he has listened to me & included my feelings in my care! I am happy to have him as my endocrinologist!

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November 17, 2024

5.0

He's an excellent doctor

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November 12, 2024

5.0

Dr. Bayer is an exceptional doctor. He is wise. He is personable. He listens.

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November 12, 2024

5.0

Extremely caring and he listens.

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November 08, 2024

5.0

He's a great doctor

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November 06, 2024

5.0

I like Dr Bayer; he keeps me informed as to needed tests, the results of tests, and any medicines that need to be changed.

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November 02, 2024

5.0

Great doctor!

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October 31, 2024

5.0

He knows his stuff, he undrrstands my perspective, and he's very pleasant.

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October 31, 2024

5.0

Takes time with me and doesn't rush appointment

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October 31, 2024

5.0

He cared for my parents at the end of their lives and then became my doctor for diabetes a few years later. I trust him. He is thorough with exams and explalnations.

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October 30, 2024

5.0

As a retired family doc, I used to refer patients to him preferentially.

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October 29, 2024

5.0

All staff were polite and professional. And I sensed that they were genuinely concerned about me and my circumstances.

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October 24, 2024

5.0

He's a great Dr makes me feel very comfortable listens well and does not rush an appointment I feel I can trust him with all decisions wish there were more like him

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October 23, 2024

5.0

competent doctor who really listens

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October 22, 2024

5.0

Wonderful Dr. Very nice , explains everything and makes you feel comfortable.

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October 20, 2024

5.0

He's awesome

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October 18, 2024

5.0

Dr Bayer is personable, he is a good listener, and allows me the time to discuss my symptoms and concerns. He is very thorough.

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October 17, 2024

5.0

Very knowledgeable

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October 05, 2024

5.0

Excellent in everything

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October 03, 2024

5.0

He's very knowledgeable and experienced

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October 02, 2024

5.0

Does a great job but appointments are limited (long wait to schedule).

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September 30, 2024

5.0

Dr. Bayer views every thing on your chart and discusses. Tells you where improvement is needed and also what your doing right to stay healthy. All around he is such a positive Doctor. I am so happy to have found this Doctor.

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September 30, 2024

5.0

Alway very caring and see all the details of your health very helpful main my health very well from long time ago

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September 25, 2024

5.0

Great & caring Doctor

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September 25, 2024

5.0

Dr. Bayer is top of the line in his field. Awesome guy, very personable.

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September 23, 2024

5.0

Caring and not aloof.

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September 19, 2024

5.0

Dr Bayer is extremely thorough and listens to my concerns and genuinely cares about his patients

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September 16, 2024

5.0

He remains knowledgeable in this area.

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Disclosures

William C. Bayer, MD reported no external professional relationships for calendar year 2024.

External Professional Relationships

Pharmaceutical, device, and biotechnology companies frequently collaborate with basic scientists and physicians within an academic medical center to help advance science and improve patient care. These relationships are important in achieving scientific breakthroughs and in establishing the effectiveness and safety of promising new therapies. In order to assure objectivity in clinical research and patient care, the Northwestern University Feinberg School of Medicine (Feinberg), Northwestern Memorial HealthCare, Children's Hospital of Chicago Medical Center, and the Shirley Ryan AbilityLab have adopted integrity policies that require research and clinical faculty (in full-time, part-time, and unpaid/voluntary categories) to report compensated and uncompensated external industry relationships. Patients are encouraged to discuss these disclosures with their physician as well as to inquire as to how these relationships are overseen by Feinberg. To learn more about our Disclosure and Professional Integrity Policy, and the conflict of interest policies of our joint affiliate survey partners, please go to our Office for Regulatory Affairs Policies page.

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