William C. Bayer, MD

4.9

1351 ratings Read Reviews

Northwestern 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

At Northwestern Medicine, our patient’s feedback is important to us. While different care providers have their own unique strengths, we strive to be as transparent as possible with our quality of care.

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Overall Rating

4.9

4.9

1351 Ratings

Reviews from Patients

81 Reviews

Reviews from Patients

81 Reviews

April 16, 2024

5.0

Dr Bayer is the best Endocrinologist I've found. Friendly and willing to answer all questions.

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April 15, 2024

5.0

He truly cares about my health

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April 15, 2024

5.0

Dr.Bayer is very caring and knowledgeable.

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April 11, 2024

5.0

Great Doctor

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April 10, 2024

5.0

Competent, supportive, trustworthy. He is the best endocrinologist I had so far.

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April 05, 2024

5.0

Keeps it real

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April 04, 2024

5.0

Dr Bayer is very knowledgeble and also looks at all of my recent medical tests to give me an opinion. I didn't know that my glucose was too high, yet he alerted me and ordered more testing. He's too busy to fit me for another appt to deal with my possible diabetes, so will hope me PCP can and will handle it.

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April 03, 2024

5.0

Everything is good for me. Thx

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March 27, 2024

5.0

Listed above.

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March 26, 2024

5.0

Professional, does not rush you, answers questions and gives great care.

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March 25, 2024

5.0

Great and caring doctor, very professional

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March 25, 2024

5.0

Professional and knowledgeable

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March 16, 2024

5.0

Dr Bayer is excellent. Very thorough and takes time to explain and answer questions took time to fix all the paperwork problems I was having. I have been with him for 35 yrs. Hoping for lots more

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March 13, 2024

5.0

Dr Bayer is a professional with great approach to helping patients understand the full scope of their medical challenges. He was kind, patient, thorough, and attentive. I did not feel rushed. He offered details that I asked for and provided referral for additional care as needed.

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March 12, 2024

5.0

Dr Bayer is approachable and professional and kind

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March 11, 2024

5.0

I find him knowledgeable and have confidence in his diagnosis and treatment.

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March 05, 2024

5.0

He is a good listener, he is kind. He is a good and intelligent doctor.

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March 04, 2024

5.0

Very kind and caring doctor

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February 28, 2024

5.0

Dr. Bayer is knowledgeable, trusted and experienced. He is also kind and encouraging.

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February 27, 2024

5.0

Friendly and open to listen.

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February 26, 2024

5.0

Excellent care. Knowledge. Informs patient for all options. Caring. Friendly. Compassionate. Good humor.

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February 22, 2024

5.0

On time and very professional.

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February 21, 2024

5.0

Dr. Bayer is fabulous and he listens. He is empathetic and is caring. Dr. Bayer is highly educated and is current with clinical studies and data.

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February 20, 2024

5.0

The best

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February 19, 2024

5.0

Dr Bayer is Professional and attentive

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February 16, 2024

5.0

Great doctor/care provider

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February 14, 2024

5.0

He was pleasant, good bedside manner, and knowledgeable.

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February 14, 2024

5.0

Outstanding doctor

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February 14, 2024

5.0

He's very professional and understanding

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February 13, 2024

5.0

Dr. Bayer continues to offer usable suggestions and helpful advice. He became aware of additional medical issues with me and tried to offer some positive advice.

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February 13, 2024

5.0

As I mentioned already above, Dr William Bayer is an outstanding Endocrinologist, who has managed to get my thyroid condition under perfect control. I would highly recommend Dr. Bayer to anyone.

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February 12, 2024

5.0

Always listens to your concerns, and answers all your questions.

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February 12, 2024

5.0

Dr. Bayer is the best person I ever had for handling my health problem.

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February 12, 2024

5.0

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

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February 07, 2024

5.0

Truly listens

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January 29, 2024

5.0

Excellent listener and years experience is outstanding. And he is a genuine person.

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January 27, 2024

5.0

Been with Dr Bayer for years. He knows my condition and has developed a level of high trust with me.

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January 26, 2024

5.0

Very good doctor

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January 26, 2024

5.0

He goes above and beyond to make sure you are well taken care of

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January 24, 2024

5.0

Dr. Bayer is very down to earth and very easy to talk to about absolutely anything.

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January 24, 2024

5.0

doctor explain well and show concern for my health

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January 22, 2024

5.0

Good doctor and personable

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January 22, 2024

5.0

He is very thorough and personable. He listens

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January 21, 2024

5.0

thorough, personable, love his clothing choices( that's a bonus. wouldn't choose a physician on that alone). a very interesting man, and a great doctor.

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January 19, 2024

5.0

He is very caring and makes me feel like he really cares

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January 16, 2024

5.0

Destination information on health concern. Advised why there is no need for addtional changes with medication.

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January 10, 2024

5.0

Awesome doctor

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January 10, 2024

5.0

Dr Bayer is GREAT!! Very knowledgeable and patient! Answered all my questions.

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January 08, 2024

5.0

Very through.

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January 02, 2024

5.0

He is a very good communicator.

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December 27, 2023

5.0

He goes through your chart and insures every lab is up to date and shares all his concerns and/or the patients.

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December 27, 2023

5.0

Great Doctor. He listens and gets to the point. He has definitely help me over the years to get my numbers in line.

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December 20, 2023

5.0

He is the best of the best. Focused, comprehensive, compassionate, all the elements you want in a Doctor. A superb professional for many years. Bravo!

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December 19, 2023

5.0

Dr. Bayer is absolutely amazing and will take such good care of you.

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December 14, 2023

5.0

Excellent attention to my symtons and medical concerns.

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December 14, 2023

5.0

Been a patient for over 20 years and had nothing but outstanding attention and care

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December 13, 2023

5.0

Dr. very friendly & kind

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December 11, 2023

5.0

Great doctor. Great bedside manner

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December 07, 2023

5.0

Doesnâ€™t prescribe all kinds of meds. Right to the point.

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December 06, 2023

5.0

Expert,professional,conversational.

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December 06, 2023

5.0

I feel he is thorough and discusses all levels that blood work indicates. He is friendly and personable. I see him on a yearly + basis but he remembers me.

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December 06, 2023

5.0

Found him experienced and informative.

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December 05, 2023

5.0

Listens well, answers all questions

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December 04, 2023

5.0

very understanding

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December 04, 2023

5.0

Heâ€™s an incredible doctor and compassionate person. I know Iâ€™m in good hands.

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December 04, 2023

5.0

As stated, I like Dr Bayer. I feel comfortable with him and I appreciate his allowing me to explain things and he always answers my questions.

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November 30, 2023

5.0

Dr Bayer is an excellent doctor and very through

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November 28, 2023

5.0

He is very caring and explains things welll.

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November 27, 2023

5.0

He listens to your concerns and don't rush you out

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November 27, 2023

5.0

I love his personality! He always puts me at ease because he is very knowledgeable, professional, caring and friendly.

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November 25, 2023

5.0

Excellent attention

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November 20, 2023

5.0

He knows his stuff and answered all my questions

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November 20, 2023

5.0

He is friendly, skilled and professional.

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November 19, 2023

5.0

Caring and professional all with amazing bedside manner

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November 15, 2023

5.0

Heâ€™s BRILLIANT! Heâ€™s professional; knowledgeable; trustworthy; highly-intelligent; a good listener to patientâ€™s questions; courteous; and an enjoyable bedside manner.

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November 15, 2023

5.0

I have been a patient for his for a very long time. I also have referred my daughter who has been seeing for many years and my sister. We are all extremely happy with his care

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November 14, 2023

5.0

He's a new doctor for me and I like him

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November 13, 2023

5.0

Dr. Bayer was welcoming and took time to answer any questions I had.

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November 13, 2023

5.0

I respect his knowledge and love his attitude and ability to communicate. I trust him.

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November 08, 2023

5.0

I value his decisions.

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November 08, 2023

5.0

Have been a patient of Dr. Bayerâ€™s since 1999 and canâ€™t imagine trusting anyone else with my diabetes care.

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November 04, 2023

5.0

Personal, thorough, explains things well, & ask questions.

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October 30, 2023

5.0

He is very understanding, knowledgeable & great bedside manner!!

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October 28, 2023

5.0

Exceptional care.

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October 27, 2023

5.0

Attention to detail and a wide scientific knowledge of the endocrine system.

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October 24, 2023

5.0

Dr Bayer clearly explains all tests and procedure results.

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October 18, 2023

5.0

The Chi in Indian caring attitude of the doctor

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October 18, 2023

5.0

Kind and caring. One of the truly finest doctors at Northwestern Medicine.

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October 17, 2023

5.0

Dr. Bayer actually listens to what I say and responds accordingly.

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October 11, 2023

5.0

Very nice staff

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October 10, 2023

4.0

They just need to run on time. I know things happpen but if your appointment is at a certain time you should be seeing the physician within 15 mins of the start of the appointment

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October 10, 2023

5.0

I have been seeing him for years and I and very pleased with the care he has given me

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October 10, 2023

5.0

I would highly recommend Dr. Bayer for care to others based on my own experience with him. Dr. Bayer actually cares about his patients and that makes all the difference.

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October 09, 2023

5.0

professional and convenient.

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October 09, 2023

5.0

Heâ€™s honest, caring and really listens to my needs.

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October 09, 2023

5.0

He is wonderful, knowledgable and caring.

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October 09, 2023

5.0

Heâ€™s very respectful of me and always happy to see me.

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October 09, 2023

5.0

While I would want to recommend Dr Bayer as he has kept my diabetes and other health issues under control. However I hesitate to recommend him because it is already difficult to get an appt with him. He is too popular!

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October 09, 2023

5.0

Knowledgeable, supportive, trustworthy

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October 07, 2023

5.0

I've seen Dr Bayer for about 20 years, long before he hooked up with NWM, his practice was better before NWM

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Disclosures

Industry Relationships

Consulting / Related Activities

Faculty member engaged in activities such as speaking, advising, consulting, or providing educational programs for the following companies or other entities

AbbVie, Inc.
IQVIA
Meetings and Events International
Novo Nordisk A/S

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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