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Department Endocrinology, Diabetes and Metabolism
Primary Location Cleveland Clinic Main Campus
Type of Doctor Both Adults and Children & Adolescents
Languages English
Surgeon No
Cleveland Clinic Main Campus
Primary Location

Cleveland Clinic Main Campus


Additional Locations

Specialties & Treatments

Treatment & Services

  • Adolescent Endocrinology
  • Cardiovascular Disease Risk Prevention
  • Diabetes Center
  • General Endocrinology
  • Male Infertility Testing
  • Medical Weight Management
  • Radioactive Iodine Treatment
  • Thyroid Aspiration
  • Thyroid Ultrasound
  • Thyroid Ultrasound and Biopsy
View all 10 Treatment & Services +

Specialty in Diseases & Conditions

  • Acromegaly
  • Addison's Disease
  • Adrenal Disorders
  • Adrenal Insufficiency
  • Adrenal Tumors
  • Adrenocortical Carcinoma
  • Adrenoleukodystrophy (ALD)
  • Alopecia Areata
  • Amenorrhea
  • Androgen Deficiency (Low Testosterone)
  • Androgen Excess
  • Beta-Cell Disorders
  • Bone Disorders
  • Calcium Disorders
  • Carcinoid Syndrome
  • Conn's Syndrome
  • Cushing's Syndrome
  • Diabetes
  • Diabetes, Gestational
  • Erectile Dysfunction
  • Familial Multiple Endocrine Neoplasia
  • Fasting Hypoglycemia
  • Flushing Syndromes
  • Galactorrhea
  • Goiter
  • Growth Hormone Deficiency
  • Growth Hormone Excess
  • Gynecomastia
  • Hair Loss
  • Hair Loss in Women
  • High Cholesterol
  • Hirsutism
  • Hyperaldosteronism
  • Hyperandrogenism
  • Hypercalcemia
  • Hyperprolactinemia
  • Hypertension - High Blood Pressure
  • Hyperthyroidism
  • Hypertriglyceridemia
  • Hypocalcemia
  • Hypogonadism
  • Hypoparathyroidism
  • Hypophysitis
  • Hypopituitarism
  • Hypothyroidism
  • Ketogenic Diet
  • Klinefelter Syndrome
  • Male Infertility
  • Menopause, Male
  • Metabolic Diseases
  • Metabolic Syndrome
  • Neuropathy - Diabetic
  • Obesity
  • Osteopenia
  • Osteoporosis
  • Panhypopituitarism
  • Parathyroid Disease
  • Pheochromocytoma
  • Pituitary Disorders
  • Pituitary Tumors
  • Polycystic Ovary Syndrome
  • Primary Hyperaldosteronism
  • Prolactin Excess States
  • Prolactinoma
  • Pseudohypoparathyroidism
  • Reactive Hypoglycemia
  • Secondary Hyperparathyroidism
  • Sexual Dysfunction
  • Sexual Hormone Disorders
  • Tertiary Hyperparathyroidism
  • Thyroid and Pregnancy
  • Thyroid Cancer
  • Thyroid Disease
  • Thyroid Nodule
  • Vitamin D Deficiency
View all 75 Specialties +


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Education & Professional Highlights

Education & Professional Highlights


Education & Fellowships

Fellowship - Mayo Clinic
Rochester, MN USA

Residency - Duke University Medical Center
Internal Medicine
Durham, NC USA

Internship - Duke University Medical Center
Internal Medicine
Durham, NC USA

Medical Education - Johns Hopkins University School of Medicine
Baltimore, MD USA

Undergraduate - University of Michigan
Ann Arbor, MI USA


  • Internal Medicine
  • Internal Medicine - Endocrinology, Diabetes and Metabolism

Specialty Interests

Type I and Type II diabetes, adult growth hormone deficiency, hypothyroidism, hyperthyroidism, thyroid nodule, hypogonadism, pituitary adenoma, adrenal insufficiency, hypercalcemia

Research & Publications

Research & Publications

See publications for Robert Zimmerman, MD.

(Disclaimer: This search is powered by PubMed, a service of the U.S. National Library of Medicine. PubMed is a third-party website with no affiliation with Cleveland Clinic.)

Industry Relationships

Industry Relationships

Cleveland Clinic physicians and scientists may collaborate with the pharmaceutical or medical device industries to help develop medical breakthroughs or provide medical expertise or education. Cleveland Clinic strives to make scientific advances that will benefit patient care and support outside relationships that promise public benefit. In order for the discoveries of Cleveland Clinic physicians' and scientists' laboratories and investigations to benefit the public, these discoveries must be commercialized in partnership with industry. As experts in their fields, Cleveland Clinic physicians and scientists are often sought after by industry to consult, provide expertise and education.

To assure professional and commercial integrity in such matters, Cleveland Clinic maintains a program that reviews these collaborations and, when appropriate, puts measures in place to minimize bias that may result from ties to industry. Cleveland Clinic publicly discloses the names of companies when (i) its physicians/scientists receive $5,000 or more per year (or, in rare cases, equity or stock options) for speaking and consulting, (ii) its physicians/scientists serve as a fiduciary, (iii) its physicians/scientists receive or have the right to receive royalties or (iv) its physicians/ scientists hold any equity interest for the physician's/scientist's role as inventor, discoverer, developer, founder or consultant.* In publicly disclosing this information, Cleveland Clinic tries to provide information as accurately as possible about its physicians' and scientists' connections with industry.

As of 10/25/2022, Dr. Zimmerman has reported no financial relationship with industry that is applicable to this listing. In general, patients should feel free to contact their doctor about any of the relationships and how the relationships are overseen by Cleveland Clinic. To learn more about Cleveland Clinic's policies on collaborations with industry and innovation management, go to our Integrity in Innovation page.

Public Health Service-Reportable Financial Conflicts of Interest. Cleveland Clinic scientists and physicians engage in basic, translational and clinical research activities, working to solve health problems, enhance patient care and improve quality of life for patients. Interactions with industry are essential to bringing the researchers' discoveries to the public, but can present the potential for conflicts of interest related to their research activities. Click here to view a listing of instances where Cleveland Clinic has identified a Public Health Service (PHS)-Reportable Financial Conflict of Interest and has put measures in place to ensure that, to the extent possible, the design, conduct and reporting of the research is free from bias.

* Cleveland Clinic physicians and scientists subscribe to the guidance presented in the PhRMA Code on Interactions with Healthcare Professionals and the AdvaMed Code of Ethics on Interactions with Health Care Professionals. As such, gifts of substantial value are generally prohibited.

Patient Satisfaction Reviews

196 Patient Satisfaction Reviews

The Patient Satisfaction Rating is an average of all responses to the care provider related questions shown below from our nationally-recognized Press Ganey Patient Satisfaction Survey. Patients that are treated in outpatient or hospital environments may receive different surveys, and the volume of responses will vary by question.

Responses are measured on a scale of 1 to 5 with 5 being the best score.

The comments are submitted by patients and reflect their views and opinions. The comments are not endorsed by and do not necessarily reflect the views of Cleveland Clinic.

Overall Star Ratings
4.8 out of 5
Explains 4.8
Courtesy, Respect & Concern 4.8
Patient Rating of Doctor 4.8

34 Patient Comments

Reviewed on Aug 11, 2023

Dr Zimmerman is a wonderful physician who is very easy to talk to, understanding and compassionate. I have recommended him to quite a few of my friends and colleagues!

Reviewed on Jul 14, 2023

Dr.Zimmerman is wonderful !

Reviewed on Jul 3, 2023

I would highly recommend to other patients like myself

Reviewed on Jun 28, 2023

Dr Zimmerman is extremely knowledgeable and very empathetic. He is the best specialist we have ever been to and are fortunate to be in his care for over 7 years.

Reviewed on Jun 19, 2023

Dr. Zimmerman spent so much time listening to my concerns and working to find a solution. I honestly don't think I've ever felt more heard' by a physician.

Reviewed on Jun 19, 2023

I would fully recommend Dr. Zimmerman to anyone needing to see an endocrinologist.

Reviewed on Jun 14, 2023

Dr Zimmernann takes time to listen to the concerns of the patients and to explain questions related to my issues!!

Reviewed on May 23, 2023

Dr. Zimmerman has always gone out of his way to help me.

Reviewed on May 19, 2023

He is a very thorough doctor. I was not pleased with my diabetes care until I started with dr z.

Reviewed on May 12, 2023

Excellent Doctor very precise and knowledgeable

Reviewed on May 12, 2023

I would recommend this Doctor He is very knowledgeable and a great Doctor

Reviewed on Apr 28, 2023

Dr. Zimmerman was very professional and polite.

Reviewed on Apr 24, 2023

Excellent experience. It was my first visit with Dr. Zimmerman and I'm very comfortable knowing I'm going to get the best care possible.

Reviewed on Apr 21, 2023

Excellent Dr. Extremely knowledgeable and up to date.

Reviewed on Apr 14, 2023

Dr. Zimmerman is excellent Doctor in everything! He is very kind, answers all questions, always respectful !

Reviewed on Apr 10, 2023

Dr Zimmerman has provided excellent care in treating my diabetes . I feel so comfortable with him. The clinic staff has been wonderful to work with. Keep up the good service.

Reviewed on Mar 17, 2023

He is excellent Doctor in everything

Reviewed on Mar 13, 2023

Dr. Zimmerman is very kind, listens, answers questions, does not rush me in and out, always respectful.

Reviewed on Mar 3, 2023

Love Dr Z! He listens and answers all questions!

Reviewed on Mar 3, 2023

Love Dr Z!

Reviewed on Mar 2, 2023

Very good experience. I am grateful to have Dr. Zimmerman on my healthcare team. He took time to patiently answer my questions and allowed me to participate in shared decision making

Reviewed on Feb 16, 2023

Great Doctors and great Staff .

Reviewed on Jan 26, 2023

Dr Zimmerman is a kind and caring person who is and making such a difference for so many! Thank you sir!!

Reviewed on Jan 24, 2023

Dr. Zimmerman has been the best care provider I have ever experienced. He is very thorough.

Reviewed on Jan 20, 2023

Dr. Zimmerman is extremely knowledgeable of the endocrine field. I've been a patient of his for many years. Excellent Dr.

Reviewed on Jan 19, 2023

Dr. Zimmerman always a very good listener and always concerned about my health

Reviewed on Dec 23, 2022

I have been a patient of Dr Zimmerman for many years and consider myself very fortunate to have such a knowledgable, thorough and expert doctor who is also so kind and caring.Dr Zimmerman offers the gold standard of care for me as a patient. I have been to dozens off specialists over the years for complex medical Issues and Dr Z stands out among them all.

Reviewed on Dec 2, 2022

Dr. Z is excellent

Reviewed on Nov 15, 2022

Dr. Zimmerman was thorough in his explanation and calming

Reviewed on Nov 14, 2022

Dr. Zimmerman provided the absolute gold standard of patient care, listening closely to my concerns and providing excellent solutions. He really cares about his patients health and it is shown by his actions.

Reviewed on Oct 12, 2022

My provider is very caring and knowledgeable about my condition.

Reviewed on Sep 22, 2022

Dr Zimmerman is a very kind and caring individual who makes a big difference in my life

Reviewed on Sep 21, 2022

Very happy with my doctor and staff

Reviewed on Sep 20, 2022

I did not anticipate having a virtual visit. I was even ready to travel to the sit-in Cleveland. The only difficulty was seeing the doctor's face completely; it was not high enough in the display. Otherwise, he was very good.

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