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Department Endocrinology, Diabetes and Metabolism
Primary Location Twinsburg Family Health & Surgery Center
Type of Doctor Adults Only
Languages English
Surgeon No
Twinsburg Family Health & Surgery Center
Primary Location

Twinsburg Family Health & Surgery Center


Additional Locations

Specialties & Treatments

Treatment & Services

  • Blood Tests
  • Bone Density Testing
  • Fine Needle Aspiration
  • General Endocrinology
  • Medical Weight Management
  • Radioactive Iodine Treatment
  • Thyroid Aspiration
  • Thyroid Ultrasound
  • Thyroid Ultrasound And Biopsy
View all 9 Treatment & Services +

Specialty in Diseases & Conditions

  • Acromegaly
  • Adrenal disorders
  • Adrenal insufficiency
  • Androgen Deficiency (Low Testosterone)
  • Androgen Excess
  • Beta-cell disorders
  • Bone Disorders
  • Calcium Disorders
  • Carcinoid Syndrome
  • Cushing's Syndrome
  • Diabetes
  • Diabetes - Management
  • Diabetes, Gestational
  • Empty sella
  • Endocrine Complications of Pregnancy
  • Endocrine Disorders
  • Fasting hypoglycemia
  • Flushing Syndromes
  • Galactorrhea
  • Goiter
  • Growth hormone deficiency
  • Growth hormone excess
  • Gynecomastia
  • Hair Loss in Women
  • High Cholesterol
  • Hirsutism
  • Hyperaldosteronism
  • Hyperandrogenism
  • Hypercalcemia
  • Hyperparathyroidism
  • Hyperprolactinemia
  • Hyperthyroidism
  • Hypertriglyceridemia
  • Hypocalcemia
  • Hypogonadism
  • Hypoparathyroidism
  • Hypophysitis
  • Hypopituitarism
  • Hypothyroidism
  • Klinefelter Syndrome
  • Male Infertility Testing
  • Metabolic Bone Disease
  • Metabolic Diseases
  • Metabolic Syndrome
  • Osteopenia
  • Osteoporosis
  • Panhypopituitarism
  • Parathyroid Disease Description
  • Pheochromocytoma
  • Pituitary Cysts
  • Pituitary Disorders
  • Pituitary stalk lesions
  • Pituitary Tumors
  • Polycystic Ovary Syndrome
  • Primary Hyperaldosteronism
  • Prolactin Excess States
  • Prolactinoma
  • Pseudohypoparathyroidism
  • Reactive hypoglycemia
  • Secondary Hyperparathyroidism
  • Tertiary hyperparathyroidism
  • Thyroid and pregnancy
  • Thyroid Cancer
  • Thyroid Disease
  • Thyroid Nodule
  • Vitamin D Deficiency
View all 66 Specialties +


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About Guy Mulligan, MD

Dr. Guy Mulligan has been appointed as Associate Staff in Endocrinology, Diabetes and Metabolism as of July 2010.  Dr. Mulligan graduated from medical school at the University of Toledo, Ohio in 2005.  He completed his medical residency at the University of Michigan, Ann Arbor, Michigan, in 2008.  He completed his fellowship training in endocrinology at the Cleveland Clinic, Cleveland, Ohio in 2010.  He participated in clinical research during his endocrinology fellowship in the areas of vitamin D therapy and inferior petrosal sinus sampling in the diagnosis of ACTH-dependent Cushing's syndrome.  He enjoys evaluating and treating a wide variety of problems within the field of endocrinology, diabetes and metabolism.
Education & Professional Highlights

Education & Professional Highlights


Education & Fellowships

Fellowship - Cleveland Clinic
Cleveland, OH USA

Residency - University of Michigan Health System
Internal Medicine
Ann Arbor, MI USA

Medical Education - University of Toledo College of Medicine
Toledo, OH USA

Undergraduate - College of Wooster
Wooster, OH USA


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

Specialty Interests

Type 2 diabetes mellitus, insulin resistance/pre-diabetes/PCOS, hyperthyroidism, thyroid nodules, primary hyperparathyroidism, hypothyroidism in pregnancy, male hypogonadism, pituitary adenoma, hyperprolactinemia, osteoporosis

Research & Publications

Research & Publications

See publications for Guy Mulligan, 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 1/4/2023, Dr. Mulligan 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

256 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
4.9 out of 5
Explains 4.9
Courtesy, Respect & Concern 4.9
Patient Rating of Doctor 4.9

57 Patient Comments

Reviewed on Dec 13, 2022

Doctor Was Polite and Very Easy To Understand When Describing My Condition

Reviewed on Dec 13, 2022

Doctor Provided An Overview Of Medical Condition and When One Aspect Was Discussed, I Was Given A Clear and ConsiceResponse

Reviewed on Dec 2, 2022

I have had many doctors, the best being my oncologist Dr. Dergham. Dr. Mulligan showed the same empathy and care. He never made me feel bad about my weight or lifestyle choices.I am really looking forward to working with him.

Reviewed on Nov 22, 2022

Excellent doctor and staff!

Reviewed on Oct 5, 2022

The best doctor I have! He listens. He diagnoses accurately. The plan of care is a mutual decision. It is then put into writing in notes given to me at the conclusions of the appointment after we both look at it and go over the print out. So very helpful to keep patients complainant thru clear concise directions.

Reviewed on Oct 5, 2022

Care by Dr Mulligan has been efficient for access to appointments and my chart messages.

Reviewed on Oct 4, 2022

Excellent visit, Dr. Mulligan was very attendant to my concerns and took the time to discuss options.He didn't rush the appointment and made sure we were on the same page as to finding a solution.

Reviewed on Sep 27, 2022

Listened to all my problems. First face to face since Dr. Mehta left. Explained labs very thorough.

Reviewed on Sep 23, 2022

I've been through a half dozen endo's - I've had issues with staff & doctor alike... I've had NONE here.

Reviewed on Sep 19, 2022

Dr. Mulligan is amazing! He's very knowledgeable, understanding, and very easy to talk to and discuss things with.

Reviewed on Sep 16, 2022

Dr. Mulligan took time to explain insulin resistance and some meds to help me overcome it and get back on track. I really appreciate the time he took with me to explain these things even though I am a nurse. He did not assume that I may have knew already information and went in depth into how insulin works in the body and over the medications and supplements that we might be able to use to help me improve.

Reviewed on Aug 25, 2022

Dr. Mulligan is a very knowledgeable and compassionate physician.

Reviewed on Aug 25, 2022

Dr. Mulligan is an outstanding physician. They "broke the mold" when they made him. He is kind, a good listener, professional and has great work ideas. I consider it a privilege to be his patient and have confidence that he can help me.

Reviewed on Aug 25, 2022

Dr Mulligan was outstanding. Support person was scary. Had to wait several months for an appointment, but I accept that for a top notch physician.

Reviewed on Aug 25, 2022

Dr Mulligan spend time explaining complicated blood work values to me unitil understood It. He listens, explains and is very concerned about me. Then he referred me back to Speech Therapist for more treatment. Thank you!!

Reviewed on Aug 19, 2022

So grateful for Dr Mulligan patience he is an Excellent doctor.

Reviewed on Aug 18, 2022

Dr. Mulligan is the best!

Reviewed on Aug 17, 2022

Everyone at this location is exceptional at their profession and very friendly. I enjoy going to see this doctor. The nicest experience anyone could ever expect.

Reviewed on Aug 12, 2022

I'm am very happy with my doctor's ability to help me to feel my best.

Reviewed on Aug 4, 2022

Dr. Mulligan explained the procedure and was gentle and respectful.

Reviewed on Aug 2, 2022

Dr. Mulligan is an exceptional physician and care provider.

Reviewed on Jul 29, 2022

Dr. Mulligan is a great doctor so I expected to have to wait a couple weeks for an appointment with him.

Reviewed on Jul 29, 2022

Dr. Mulligan listened to my concerns more than any other doctor I've seen for my current issues.

Reviewed on Jul 25, 2022

Dr. Mulligan always does a wonderful job he is a very caring physician who isn't asking me when I first walk in the door have you thought about bariatric surgery like my primary care doctor does every visit

Reviewed on Jul 8, 2022

Dr Mulligan is amazing and unique. He is so interested in my symptoms and my feedback about what is working and what isn't. Truly fabulous physician.

Reviewed on Jul 7, 2022

He's a smart & caring doctor who answered all my questions & concerns. He went through the ultrasound with me and explained it in detail.

Reviewed on Jul 1, 2022

Dr answered all my questions and addressed all concerns. He spend a lot of time with me and didn't rush the appointment

Reviewed on Jun 17, 2022

Dr. Mulligan is a caring, professional, excellent doctor. I really like him!

Reviewed on Jun 7, 2022

Dr Mulligan is very informative and explains things clearly.

Reviewed on Jun 7, 2022

My best doctor

Reviewed on May 25, 2022

Dr. Mulligan's staff is always a pleasure to work with.

Reviewed on May 25, 2022

Dr. Mulligan is always professional, attentive and caring for all appointments

Reviewed on May 24, 2022

I would recommend Dr. Mulligan highly. I wasEmbarrassed by a nurse in the Twinsburg ER duringMarch of 2021. I was chastised for crying and amIn my 80's!

Reviewed on May 20, 2022

Knowledgeable, open minded, listens well to me , hears my concerns and acts accordingly GREAT Doctor!!

Reviewed on May 18, 2022

Dr. Guy Mulligan is THE BEST endocrinologist I have ever had. He is thorough and answers all my questions. We make decisions together about my care. I also GREATLY appreciate his holistic approach to my care. Though we focus on addressing the issues that bring me to him (e.g., hypothyroidism, insulin resistance), his manner is holistic. His bedside manner is outstanding. I cannot say enough positive things about his bedside manner, knowledge, approach to decision-making, etc.

Reviewed on May 5, 2022

Dr. Mulligan was friendly, concerned, and professuonal. Everything went well.

Reviewed on Apr 28, 2022

Dr mulligan is kind and listens. And takes his time with your concerns

Reviewed on Apr 26, 2022

Doctor sanitized his hands before and after examining my thyroid.

Reviewed on Apr 19, 2022

Dr. Mulligan is a caring professional who has my. Confidence.

Reviewed on Apr 19, 2022

Dr. Mulligan has provided top notch care to me for years.

Reviewed on Apr 19, 2022

Clinic is where I have confidence and thus most of my doctors.

Reviewed on Apr 12, 2022

Dr. Guy Mulligan always explains my test results in a detailed manner which is easily understood by me. He reviews my past tests spanning the five years he has treated me and points out his opinion of the trends seen in test results. He spends sufficient tome during my appointments and answers all my questions. Dr. Mulligan is an excellent educator and communicator. I was most impressed with how he performed the fine needle aspiration biopsy of my thyroid nodule. His assistant was very supportive and managed any discomfort during the biopsy with her application of ice as directed by Dr. Mulligan. Both are to be commended.

Reviewed on Apr 8, 2022

Dr. Mulligan has always been an endocrinologist I'd recommend to anyone!

Reviewed on Apr 8, 2022

Outstanding physician. The best of the best.

Reviewed on Apr 6, 2022

Dr Mulligan is always very professional and takes the time to answer all of my questions very well. We always discuss my treatment plan, next steps, and and any changes that might be made. I have complete confidence in Dr Mulligan's care, and truly appreciate his caring kindness towards me.

Reviewed on Apr 5, 2022

I wanted to try something new and Dr. Mulligan was very familiar with thyroid medication. If I have any issues I know that he would be able to solve them. I have confidence in knowing that he will be there for me.

Reviewed on Apr 5, 2022

I look forward to working with Dr. Mulligan and his staff.

Reviewed on Mar 25, 2022

Every thing was great !!.!!!!!!! Dr. Mulligan is wonderful. !!!!!!!!

Reviewed on Mar 18, 2022

Really hard getting appointments with Dr. Mulligan, especially in person.

Reviewed on Mar 15, 2022

Dr. Mulligan has an excellent bedside manner. He is so patient and respectful and shows genuine concern for me as a person. I love that he allows you to participate in making decisions about your treatment.

Reviewed on Mar 10, 2022

Dr. Mulligan was very thorough with me during my first visit. He seems very knowledgeable and caring he doesn't just act like I'm a number. I trust him to get me back to feeling 100 percent again.

Reviewed on Feb 16, 2022

Dr. M is excellent amd knowledgable. He is a safe practitioner with great bedside manner. The student was also very nice.

Reviewed on Feb 15, 2022

Dr Mulligan listened and involved me in choosing new medication to increase my energy level. He is very kind !

Reviewed on Feb 1, 2022

Dr Mulligan was very thorough and spent time explaining things. Was not rushed

Reviewed on Jan 26, 2022

Great doctor

Reviewed on Jan 24, 2022

Always loved Dr Mulligan

Reviewed on Jan 21, 2022

Dr. Mulligan is always kind and concerned and makes me feel like I'm important

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