Summary

Dr. William Bayer treats hyperlipidemia, high cholesterol in children and teens, and type 2 diabetes mellitus, and performs MRI of the lumbar spine. He practices endocrinology, diabetes, and metabolism and has 40 years of experience. Dr. Bayer is affiliated with Northwestern Medicine Central Dupage Hospital.

He completed his residency at Loyola University Medical Center in 1989 and his fellowship there in 1991, and sees patients in Bloomingdale, Illinois. He speaks English and Spanish. Patients on Vitals rate Dr. Bayer 4 out of 5.

Overview based on verified provider data

Quick Facts

  • accepting new patients
  • 4
  • 40 years of experience
  • 26 insurance plans accepted
  • speaks English, Spanish
  • Loyola University Medical Center
  • 9 written reviews
  • 2 specialties
  • 16 areas of expertise
  • 1 hospital affiliation
  • 1 office location
  • Male

Patients’ Perspective

  • Gave an accurate diagnosis
  • Had a good bedside manner
  • Spent time with me

Office Location

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William C. Bayer, MDDr. Melissa McGee, DNPDr. Rabab Zehra Jafri, MDDr. Bekir Suveyd
Endocrinology, Diabetes & MetabolismEndocrinology, Diabetes & MetabolismEndocrinology, Diabetes & MetabolismEndocrinology, Diabetes & Metabolism
Accepts New Patients Accepts New Patients Accepts New Patients Accepts New Patients
4 
0 
5 
0 
40 Years of Experience 16 Years of Experience 11 Years of Experience
No Virtual Visit Option No Virtual Visit Option Virtual Visit Available Virtual Visit Available
Speaks English, Spanish Speaks English, Spanish Speaks English, Hindi, Urdu Speaks English, Arabic
Bloomingdale , ILHighwood , ILChicago , ILChicago , IL
Med School: Loyola University Stritch School of Medicine Med School: Aga Khan University Medical College Med School: Alfaisal University College Of Medicine
Current Profile
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Insurance Plans Accepted by William C. Bayer

  • Aetna
  • Aetna - Medicare
  • Aetna Better Health - Medicaid (Managed)
  • Ambetter
  • AmeriGroup
  • Blue Cross Blue Shield
  • Blue Cross Blue Shield - PPO
  • Blue Cross Blue Shield of Illinois
  • Cigna
  • Health Alliance
  • Humana
  • Medicaid - Medicaid
  • Medicaid - Medicaid (Managed)
  • Medicare
  • Medicare - Medicaid
  • Medicare - Medicare
  • Meridian Health Plan - Medicaid (Managed)
  • Meritain Health
  • Molina Healthcare - Medicaid (Managed)
  • Nippon Life Benefits
  • North Shore LIJ CareConnect
  • North Shore LIJ CareConnect - IPA
  • Priority Health
  • Tricare
  • UnitedHealthcare
  • UnitedHealthcare - Medicare

Medical Specialties

William C. Bayer has the following 2 specialties

Specialty Expertise

William C. Bayer has the following 16 areas of expertise

  • Acromegaly
  • Addison Disease
  • Cushing Disease
  • Diabetes
  • Diabetes Mellitus, Type 1
  • Diabetes, Type 2
  • Endocrinology
  • Endocrinology & Metabolism
  • Fatigue
  • Gland Issues
  • Hormones
  • Hyperthyroidism
  • Hypopituitarism
  • Hypothyroidism
  • Osteoporosis
  • Thyroid Diseases

Certifications, License, & Education

40 Years Experience

William C. Bayer holds an expired medical license in the state of Illinois.

Medical License

Medical Doctor with an expired medical license in the state of Illinois that expired in 2026.

Education & Training

Fellowship

Completed their fellowship at Loyola University Medical Center in 1991.

Residency

Completed their residency at Loyola University Medical Center in 1989.

Medical School

Graduated from Loyola University Stritch School of Medicine in 1986.

NPI Number

William C. Bayer's NPI number is 1528162898.

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Frequently Asked Questions

Which hospitals is William Bayer affiliated with?
William Bayer is affiliated with Northwestern Medicine Central Dupage Hospital.
How can I make an appointment with William Bayer?
You can find contact information for William Bayer here on Vitals.
What languages does William Bayer speak?
William Bayer speaks English and Spanish.
Where is William Bayer's office located?
William Bayer's office is located at 233 S Gary Ave, Bloomingdale, IL, 60108.
Does William Bayer accept my insurance?
You can see the insurance plans that William Bayer accepts on their Vitals profile.

Data Sources

This provider profile is built using data from:

  • NPPES NPI Registry
  • State medical licensing boards
  • Healthcare system and provider network data

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