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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
  • Diabetes Care and Treatment
  • Fine Needle Aspiration
  • General Endocrinology
  • Medical Weight Management
  • Radioactive Iodine Treatment
  • Thyroid Aspiration
  • Thyroid Ultrasound and Biopsy
View all 9 Treatment & Services +

Specialty in Diseases & Conditions

  • Adrenal Insufficiency
  • Androgen Deficiency (Low Testosterone)
  • Androgen Excess
  • Calcium Disorders
  • Cushing's Syndrome
  • Diabetes
  • Empty Sella
  • Endocrine Disorders
  • Fasting Hypoglycemia
  • Flushing Syndromes
  • Galactorrhea
  • Goiter
  • Gynecomastia
  • Hair Loss in Women
  • High Cholesterol
  • Hirsutism
  • Hyperaldosteronism
  • Hyperandrogenism
  • Hypercalcemia
  • Hyperparathyroidism
  • Hyperprolactinemia
  • Hyperthyroidism
  • Hypertriglyceridemia
  • Hypogonadism
  • Hypopituitarism
  • Hypothyroidism
  • Klinefelter Syndrome
  • Metabolic Syndrome
  • Panhypopituitarism
  • Parathyroid Disease
  • Pituitary Cysts
  • Pituitary Disorders
  • Pituitary Stalk Lesions
  • Pituitary Tumors
  • Polycystic Ovary Syndrome
  • Primary Hyperaldosteronism
  • Prolactin Excess States
  • Prolactinoma
  • Reactive Hypoglycemia
  • Secondary Hyperparathyroidism
  • Thyroid and Pregnancy
  • Thyroid Cancer
  • Thyroid Disease
  • Thyroid Nodule
  • Vitamin D Deficiency
View all 45 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

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

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

Undergraduate - College of Wooster
Wooster, OH


  • 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 5/27/2024, Dr. Mulligan has reported the financial relationships with the companies listed below. 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

430 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 4.9
Patient Rating of Doctor 4.8

127 Patient Comments

Reviewed on May 20, 2024

This physician is very open to discussion and clarifies the plan of care which involves me.

Reviewed on Apr 26, 2024

I was not able to schedule in-person, my preference. The Scheduling Dept resisted. But, my virtual visit with Dr Mulligan was thorough, well-planned, and appreciated. I learned a lot from Dr. Mulligan. He is respectful and knowledgeable and made me feel at ease. Truly appreciated.

Reviewed on Apr 26, 2024

As noted in previous response. Dr Mulligan is knowledgeable, respectful, kind, answered all questions thoroughly and put me at ease. I am quite happy with our visit and learned a lot. Truly appreciative.

Reviewed on Apr 25, 2024

I have had Dr. Mulligan for many years and he is the best. Knowledgeable, professional, easy to talk to, listens to what I have to say and takes my concerns seriously. I am both confident in his ability and appreciative of his man or of communication.

Reviewed on Apr 23, 2024

I'm grateful that my care providers and doctors are in the Cleveland Clinic system.

Reviewed on Apr 22, 2024

Kind and respectful provider. Does not respond to MyChart messaging in a timely manner.

Reviewed on Apr 19, 2024

I can't say enough good things about Dr. Guy Mulligan. As an endocrinologist, he's at the top of the game clinically and provides excellent explanations of what is a complicated area of the body's functions. He is also pleasant, patient, and easy going with patients. I recommend him highly to family and friends who need endocrine care.

Reviewed on Apr 16, 2024

Dr Mulligan is very kind and understanding

Reviewed on Apr 12, 2024

Dr Mulligan always gives his best efforts and attention to my questions and works with me to solve them. Exceptional care!

Reviewed on Apr 8, 2024

Dr. Mulligan was very helpful and considerate in regard to listening to my current physiological symptoms and possible medication dosage changes.

Reviewed on Apr 1, 2024

Overall really like Dr. Mulligan. He really listens. Know he and his peers are busy, but would be great If Drs had more knowledge of current events of meds they are prescribing like Mounjaro.

Reviewed on Apr 1, 2024

Dr Mulligan is always thorough and attentive to my health needs and questions.

Reviewed on Mar 19, 2024

Dr. Mulligan is an excellent doctor. He gave me plenty of time to learn about my concerns and explain his plan of care. I am very pleased to have been referred to him by Dr. Mehta.

Reviewed on Mar 19, 2024

Excellent doctor

Reviewed on Mar 19, 2024

This appt was pure luck. My mother had a terrible time scheduling for the same physician so me being able to get a referral AND book an appt the next day was definitely not the norm.

Reviewed on Mar 19, 2024

Dr. Mulligan is wonderful. I wish there were more endos like him available in the satellite locations across the area.

Reviewed on Mar 18, 2024

Dr Mulligan always answers all of my questions and includes me in the discussion about my treatment and care. I truly appreciate that.

Reviewed on Mar 14, 2024

Awesome doctor. Very educational. Great experience.

Reviewed on Mar 8, 2024

Dr. Mulligan is very kind and caring and took the time to answer all of my questions without me feeling rushed.

Reviewed on Mar 8, 2024

The video visit allowed me to not have to make a 10-hour round trip drive to see Dr. Mulligan.

Reviewed on Mar 8, 2024

Great doctor, I have already recommended him to a friend.

Reviewed on Mar 1, 2024

This doctor is so popular, hard to get an appointment!

Reviewed on Mar 1, 2024

Outstanding care and excellent doctor

Reviewed on Mar 1, 2024

Excellent doctor all around

Reviewed on Feb 9, 2024

DR. Mulligan is one of the best endocrinologists I have seen. Knowledgeable, kind and caring.

Reviewed on Feb 8, 2024

Dr. Mulligan was very thorough with his review and recommendations for next steps.

Reviewed on Feb 8, 2024

Dr. Mulligan is an excellent doctor.

Reviewed on Feb 6, 2024

Outstanding doctor! Dr. Mulligan is extremely knowledgeable, a great listener, and a compassionate and caring physician.

Reviewed on Feb 6, 2024

The Dr was very thorough and responsive to my concerns. He seems like he's a very good endo and is willing to help with my weight and thyroid concerns he's just very busy. The wait time to see him was just horrible and he still hasn't reviewed my labs or responded about them.

Reviewed on Feb 6, 2024

It's very difficult to get into see Dr Mullian

Reviewed on Feb 6, 2024

Dr mulligan is a very good caring doctor!

Reviewed on Feb 6, 2024

My surgeon and Dr mulligan had different opinions. I feel they could have discussed this before my visit

Reviewed on Feb 5, 2024

Dr Mulligan is an excellent people person. Warm and genuinely caring. I'm very happy to have found a Dr like him.

Reviewed on Feb 2, 2024

Dr Mulligan is fantastic and clearly cares about his patients.

Reviewed on Feb 2, 2024

The staff is wonderful but NP visit should cost less than Dr visit.

Reviewed on Feb 1, 2024

Dr. Is very busy so you have to schedule a minimum of 6mo. Out.

Reviewed on Feb 1, 2024

Dr. Mulligan is excellent and caring and gives you plenty of time at your viist

Reviewed on Jan 30, 2024

I am a new patient for Dr Mulligan I was very please he listened to me with my concerns and my questions and helped me manage the best care plan. . I am happy he is my Endocrinologist.

Reviewed on Jan 25, 2024

Excellent doctor

Reviewed on Jan 19, 2024

I appreciate Dr. Mulligan's treatment of obesity. This is controversial now, but I suspect he is on the right side of history. Old school medicine related to obesity is not as simple as eat less move more. If it were: We would not be a country full of obesity.

Reviewed on Jan 12, 2024

Dr Mulligan is an excellent physician. He is very knowledgable, excellent communication skills, and professional

Reviewed on Jan 11, 2024

Dr Mulligan is outstanding in all regards.

Reviewed on Jan 10, 2024

I have recommended Dr. Mulligan to others but he is hard to get an appointment with because of the high demand for his services.

Reviewed on Jan 4, 2024

Dr Mulligan sets the bar very high for excellence! I credit him for saving my daughter through his expertise and care and advocacy for his patients. When I developed an endocrine problem, there was no choice but for Dr. Mulligan. Thank you

Reviewed on Jan 3, 2024

I had a fabulous appointment with Dr. Mulligan. He is one of the best diagnosticians In your system. He really listens and very empathetic.

Reviewed on Jan 3, 2024

I had a terrific experience. Dr Mulligan is compassionate and supportive.

Reviewed on Jan 3, 2024

The appointment-making process was easy and efficient. This was my first visit with this provider; I would have liked an appointment sooner, but he was booked, and I got his earliest available appointment.

Reviewed on Jan 3, 2024

This was my first appointment with Dr. Mulligan, so there was a lot of medical history gathering, and questions on my part about possible DXs. He gave be a detailed explanation of the role of the parathyroid in controlling calcium levels at an understandable level of comprehension-no condescension!

Reviewed on Dec 27, 2023

Dr.Mulligan's office is very poor at answering My Chart messages. It took 6 weeks and several texts to get an answer to a test result question. Some go unanswered.

Reviewed on Dec 27, 2023

Dr Mulligan is exceptional in taking the time to answer all of your questions, in explaining your disease, and explaining test results. He is a rare gem in the Cleveland Clinic.

Reviewed on Dec 26, 2023

Dr. Mulligan is an excellent listener, which makes him an excellent Dr.

Reviewed on Dec 18, 2023

This is the second time that a video appointment has not worked and needed to resort to a phone call. Should not be charged in full because of technical difficulties on C.C.'s side. The doctor did call me and it went well. Just not happy with the video issues.

Reviewed on Dec 13, 2023

Dr. Mulligan is top of the line when it comes to patient care and knowledge.

Reviewed on Dec 13, 2023

Dr. Mulligan listened carefully to my concerns and Inc me in care decisions

Reviewed on Dec 12, 2023

Dr. Mulligan is always fantastic. He takes time to listen so that you feel really heard. He brings up new ideas to try. We discuss all the pros and the cons so that I don't go into anything blindly. He is just great

Reviewed on Dec 1, 2023

Dr. Mulligan always takes the time to address my concerns.

Reviewed on Dec 1, 2023

Dr Mulligan is the best. He takes the time to explain everything

Reviewed on Dec 1, 2023

Dr. Mulligan is an outstanding physician. He is caring and collaborative in addressing my concerns.

Reviewed on Nov 30, 2023

Dr Mulligan is a fantastic dr.

Reviewed on Nov 30, 2023

Dr Mulligan is the best. His demeanor is very calm and it totally agrees with me. He looks at all my test and gives me an informed answer. I travel to get to him but for me it's worth. Great doctor!

Reviewed on Nov 30, 2023

Dr. Mulligan is very kind. Apologetic at the start over the delay, focused on the health issues and talked WITH us, NOT AT US. We appreciate that very much.

Reviewed on Nov 28, 2023

So so dissatisfied that I will have to see nurse practitioner instead of DR. Mulligan. This is about healthcare not how much money he can make the hospital so so disappointed..

Reviewed on Nov 24, 2023

Dr. Mulligan is a fine gentleman and an excellent endocrinologist.

Reviewed on Nov 21, 2023

Dr mulligan is very thorough and provides good explanations of his thinking in terms of treatment.

Reviewed on Nov 17, 2023

Dr. Mulligan is an exceptional provider. He is extremely knowledgeable and truly takes the time to care for the patients needs. I recommend Dr. Mulligan to anyone dealing with his areas of expertise.

Reviewed on Nov 17, 2023

Dr. Mulligan is an excellent physician!

Reviewed on Nov 16, 2023

Dr Mulligan has always, and continues to be a very compassionate and caring care giver. He always includes me, as the patient, in decisions.

Reviewed on Nov 15, 2023

Dr. Mulligan was patient with me, answered all of my questions thoroughly, and wished me luck! He's great!

Reviewed on Nov 10, 2023

Dr. Mulligan was very very thorough in explaining everything to me.

Reviewed on Nov 9, 2023

I highly recommend Dr. Mulligan. He's a nice man who cares about his patients. He answered all my questions.

Reviewed on Nov 9, 2023

Dr mulligan is awesome!Very patient and explains everything

Reviewed on Nov 9, 2023

Always a pleasure to meet with Dr mulligan

Reviewed on Nov 9, 2023

The Dr was very informative and explained everything so that I could understand.

Reviewed on Nov 8, 2023

Dr Mulligan is outstanding - I am so grateful for his medical care.

Reviewed on Nov 6, 2023

I have been to so many doctors and he is by far the best at listening and understanding

Reviewed on Nov 2, 2023

Dr Mulligan and STAFF are true patient care providers that represent why people go to the Cleveland Clinic seeking the best possible care

Reviewed on Nov 2, 2023

Wonderful Doctor

Reviewed on Oct 17, 2023

Dr Mulligan is a superb Doctor he gets 5 stars I would recommend him to anyone.

Reviewed on Oct 17, 2023

Dr Mulligan explains things very well.

Reviewed on Oct 17, 2023

Greatest doctor I've ever seen

Reviewed on Oct 13, 2023


Reviewed on Oct 5, 2023

Dr Mulligan took the time to go through and explain my lab results. He is always attentive and supportive.

Reviewed on Sep 28, 2023

Loved Dr mulligan but time it took to actually see him was too long. Almost 3 months

Reviewed on Sep 28, 2023

Dr Mulligan was very thorough and explained things very well.

Reviewed on Sep 28, 2023

Dr. Mulligan took time to explain and really listened. I feel confident being in his care.

Reviewed on Sep 26, 2023

I actually look forward to my appointments with Dr Mulligan.

Reviewed on Sep 21, 2023

The information provided by my doctor was very helpful.

Reviewed on Sep 19, 2023

Dr Mulligan listens,answers my questions,write down directions for me to do- very kind and reassuring!

Reviewed on Sep 18, 2023

Dr. Milligan is very kind caring doctor and I would recommend him to anyone. He's a great doctor ...

Reviewed on Sep 15, 2023

I had an appointment this past summer that I had to cancel. Dr. Mulligan's office reached out to me immediately to reschedule asap.

Reviewed on Sep 15, 2023

Dr. Mulligan is very thorough and genuinely cares about my health and well-being. He has always respected my thoughts and feelings about treatment and medications.

Reviewed on Sep 15, 2023

Whether my appointment is in-person or online, Dr. Mulligan spends the same amount of time with questions, concerns and overall care.

Reviewed on Sep 15, 2023

Dr . Mulligan provides excellent care. He has helped me successfully manage my long term health concerns. He's the first doctor to actually get the results I need. The on-line exam was helpful because of his skill and rapport. I don't really see the point of doing it virtually rather than in person.

Reviewed on Sep 15, 2023

Again, Dr. Mulligan is excellent. I just don't understand why we didn't meet in person. It seems like he spent the same amount of time with me online that he would have in person. So, really, what was the point?

Reviewed on Sep 11, 2023

Dr. Mulligan is very knowledgeable, professional, and easy to talk to. He does an outstanding job!

Reviewed on Sep 8, 2023

Best doctor I ever had. Doctor Mulligan listens to patients carefully and offer his expertise advice and recommendations on the discussed and he Is right on target.

Reviewed on Sep 8, 2023

Dr Mulligan always kindly listens to my concerns and answers my questions completely. I am very pleased with his care.

Reviewed on Sep 5, 2023

Dr. Mulligan took the time to explain all the procedure and I was grateful for that.

Reviewed on Sep 5, 2023

Dr. Mulligan is a consummate professional. His interpretations have helped immensely.

Reviewed on Aug 24, 2023

Dr. Mulligan is very thoughtful and calm with his words. He does a thorough job, contacts with test results in a timely manner and overall is an excellent doctor. I am very happy he was recommended to me from another family member.

Reviewed on Aug 24, 2023

Dr. Mulligan speaks to you as if you are a friend, not a patient or paycheck. He is very understanding of one's feelings and concerns. He explains things in a way that anyone can grasp understanding.

Reviewed on Aug 24, 2023

Dr. Mulligan was very good about providing me with information about a couple of options with new medications

Reviewed on Aug 24, 2023

Excellent provider and always taking the time and listen and show care even in a fast pace medical field and lot of patients to see but from the 1st in 2019 and present and I am thankful to find Mulligan and always taking the time putting patient first. Thank you so very much and it mean much to patients

Reviewed on Aug 23, 2023

It took years to finally find a doctor that listened to my concerns, Dr Mulligan listened & addressed them.

Reviewed on Aug 21, 2023

Dr. Mulligan is excellent. He listens and cares about me. This was my first virtual appointment. It was just like an in office.

Reviewed on Aug 18, 2023

Excellent doctor

Reviewed on Aug 18, 2023

Excellent doctor

Reviewed on Aug 14, 2023

I was extremely impressed with Dr. Mulligan's genuine caring attitude. He listened completely and thoughtfully discussed every issue and concern without feeling rushed in any way. The experience was very relaxed yet professional.

Reviewed on Aug 14, 2023

I can't say enough good things about my impression of Dr. Mulligan during my initial telemed experience.

Reviewed on Aug 10, 2023

Doctor was wonderful and took his time explaining details and I did not feel rushed through my appointment. Great experience.

Reviewed on Aug 9, 2023

The doctor listen to my concerns and put in writing a detailed plan to help me maintain my sugar levels.

Reviewed on Aug 9, 2023

Very Professional as well as staff. He answered all my questions and everyprocess that he had on paper was completed just as was written. Thus gave me some peace about having the procedure done. 5hank you Dr. Mulligan and staff

Reviewed on Aug 9, 2023

Dr Mulligan is always friendly, professional, always explains any changes, if needed.

Reviewed on Aug 8, 2023

Dr M is a model for care. He listens and helps me consider options od increasing medication while balancing side effects. He helps write for bloodwork and renewals to keep care maintaining my prescriptions and labs without needing to do extra calls before subseeuent visits. He considers both the medical decisions and the processes involved to make it easier for me.

Reviewed on Aug 7, 2023

Dr Mulligan truly cares for his patients. He listens and works to meet your concerns. I am so grateful he was my doctor and he devised a protocol for me that is actually working to a remission of the medication.

Reviewed on Aug 7, 2023

Dr Mulligans staff is very efficient and friendly

Reviewed on Aug 7, 2023

My Physician was awesome. Great job explains all of my options and treatment plan. Very good follow up.

Reviewed on Jul 28, 2023

Dr. Mulligan listen and was genuinely interested in my health needs. I look forward to a long standing relationship with him as my doctor.

Reviewed on Jul 27, 2023

Doctor spent appropriate amount of time to learn my medical problems and discuss alternative medicines. I was very impressed with his professionalism and patient caring.

Reviewed on Jul 19, 2023

Dr Mulligan is an excellent doc. Very knowledgeable, compassionate and spend much time explaining a new med. Greatly appreciate his professionalism and kindness

Reviewed on Jul 5, 2023

Unable to get an appointment within a reasonable time again if it is cancelled for some Reason by physician or patient

Reviewed on Jul 5, 2023

Excellent care provided by Dr Mulligan

Reviewed on Jun 27, 2023

Dr. Mulligan always takes the extra time to listen, and offers valuable advice. It is always a pleasure to see him!

Reviewed on Jun 9, 2023

Dr. Mulligan is excellent and very thoughtful.

Reviewed on Jun 9, 2023

Dr. Mulligan is always so kind and does his best and helping me with my diabetes. He listens with no judgments.

Reviewed on Jun 9, 2023

Dr. Mulligan really listened and understood my situation and made changes to my meds and explained it to me that made sense.

Reviewed on Jun 8, 2023

Dr Mulligan listens very well and fully explains the options I have for my care.

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