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
  • Radioactive Iodine Treatment
  • Thyroid Aspiration
  • Thyroid Ultrasound
  • Thyroid Ultrasound And Biopsy
View all 8 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 10/20/2020, 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

347 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

92 Patient Comments

Reviewed on Dec 14, 2020

one of the BEST HCP's I have ever had. he was very thorough, Dr. listened to my concerns and questions and didn't feel rushed ever. his nurse is very fast at getting a response. I couldn't say 1 bad this about this team they are awesome!

Reviewed on Dec 10, 2020

I am looking forward to having Dr. Mulligan looking into my concerns and I feel I will be greatly helped going forward.

Reviewed on Dec 10, 2020

Doctor addressed all my concerns 100 percent.

Reviewed on Dec 10, 2020

This was my first visit with this doctor. A diagnosis is yet to have been made regarding my condition. Many tests were ordered and I am awaiting the results. I feel confident that this doctor will explain the findings fully and will discuss treatment options with me in detail. I am also confident all questions that I have will be addressed and that, together, a decision will be made as to how to proceed with treatment. I felt very comfortable discussing my symptoms and concerns with this doctor immediately and felt that he was listening to what I said very closely. I am pleased that many tests were ordered to obtain a clear picture of what is causing me to feel the way I have been feeling. I believe that I will find him to be an excellent doctor as my treatment progresses.

Reviewed on Dec 10, 2020

I have had a very trying year as regards my overall health. I have had several surgical procedures as well as treatment for breast cancer. I have traveled to several locations for my treatment and I have been very pleased with the care that I have received at the Cleveland clinic. I am especially pleased that I can receive care from any doctor within the network and they are able to see my complete medical history. I believe that having an overall picture of a patient's circumstances is essential in making the most informed treatment decisions.

Reviewed on Dec 10, 2020

Dr is excellent, active listener, caring, participative in plan of care. Best dr I've ever been to.

Reviewed on Dec 7, 2020

Dr Mulligan was excellent, very detailed explanation of my issue, with all options for treatment with discussion of pros and cons of each. so glad I found him!!

Reviewed on Dec 7, 2020

I really like dr. Mulligan, that is why I stay with him even though it is so hard to get an appointment.

Reviewed on Dec 2, 2020

Dr. Mulligan was the first doctor at the Cleve Clinic that gave me the time I needed to understand my health condition and concerns.

Reviewed on Nov 30, 2020

I like Dr. Mulligan more with each visit. I got really lucky when I became one of his patients.

Reviewed on Nov 17, 2020

Dr. Mulligan is a great listener and always offers great concern and options to help resolve any issues.

Reviewed on Nov 16, 2020

This was my first visit with Dr. Mulligan and I was VERY impressed with him. Seems so competent as a doctor and entirely personable, "human-to-human".

Reviewed on Nov 12, 2020

Excellent service! Dr. Mulligan is the best!

Reviewed on Nov 11, 2020

doctor very anxious to help

Reviewed on Nov 11, 2020

Dr. Mulligan has always listened to all of my needs and problems. He takes the time to see what he can do to help make any situation better. I have referred him to so many family members and friends.

Reviewed on Nov 11, 2020

Dr. Mulligan is so caring and professional. I value his opinions.

Reviewed on Nov 11, 2020

I am very satisfied with Dr. Mulligan's service he takes the time to listen and talk about my concerns which I appreciate very much

Reviewed on Nov 11, 2020

even though Dr Mulligan has a very full schedule, they got me in the very next day! I was shocked!!!

Reviewed on Nov 11, 2020

I have had an ongoing medical problem for three years. I have been to two other endocrinologists and 2 functional doctors and one gynecologist. Dr Mulligan is the first person to listen to what I said. He diagnosed what was wrong. I could not possibly be more thankful. He is amazing

Reviewed on Nov 11, 2020

walking out the door, Dr Mulligan suggested I stop by the scheduler to get the cat scan. The lady was very kind and diligent and got me in to get the care scan the same day!!! it was a miracle!!! she went above and beyond the easy way to get it. I appreciate it so much!!!! she's the lady on the third floor corner. please tell her thank you!!!

Reviewed on Nov 5, 2020

I appreciated the fact that Dr. Mulligan listened and understood all of what I said.

Reviewed on Nov 2, 2020

every experience with the clinic has been great and Dr. Mulligan is the best!

Reviewed on Oct 27, 2020

the best doctor at the clininc

Reviewed on Oct 26, 2020

Dr Mulligan is everything anyone could want in a physician - exceedingly knowledgeable, professional, excellent communicator as well as an excellent listener.

Reviewed on Oct 21, 2020

Dr. Mulligan is very understanding and I feel I am in good hands.

Reviewed on Oct 21, 2020

Needed to see a skin doctor and Dr. Mulligan got me in the next day.

Reviewed on Oct 21, 2020

Dr. Mulligan is very kind and caring and I feel he is a great physician. I feel confident in the care that I receive from him.

Reviewed on Oct 14, 2020

excellent patient doctor compassion skills

Reviewed on Oct 14, 2020

Dr Mulligan is zn excellent Dr I recommend him to everyone with diabetes

Reviewed on Oct 6, 2020

Great experience with Dr. Mulligan and nurse Edie

Reviewed on Sep 29, 2020

Dr. Mulligan has always tried and work on the best course of treatment for me from day one. He explains everything very thorough. Very friendly and concerned about me as a patient.

Reviewed on Sep 29, 2020

*Doctor Mulligan and his staff are top notch.

Reviewed on Sep 29, 2020

I would recommend *Dr. Mulligan to any one (he's great) very caring and explains everything really well.

Reviewed on Sep 28, 2020

Dr. Mulligan is an excellent physician.

Reviewed on Sep 11, 2020

it is always a pleasure to see Dr. Mulligan

Reviewed on Sep 3, 2020

my appt was scheduled almost a year in advance. if I've had any questions between visits Dr Mulligan and his team always are available by email in my chart. great experience with him and his nurse.

Reviewed on Sep 3, 2020

Dr. Mulligan and his team are models of patient care and excellent personal interactions. He involves me in discussions about next steps and what is optimal for me, and he always remembers my past history and problem list in the review. I have already recommended him to my friends with endocrine issues.

Reviewed on Aug 21, 2020

It was a nice experience, I was glad to be able to do the virtual appointment. Dr. Mulligan is a kind and compassionate doctor, who never makes me feel rushed.

Reviewed on Aug 21, 2020

I have recommended Dr. Mulligan to several people that are now his patients.

Reviewed on Aug 18, 2020

Best doctor visit I have had regarding my thyroid care. I felt heard for the first time ever. I felt like the doctor was well equipped to deal with my issues and I finally felt like together we will be able to resolve a problem I have struggled with for decades.

Reviewed on Aug 17, 2020

Dr Mulligan was an extremely great listener and gave me a feeling that my description was well received

Reviewed on Aug 14, 2020

Dr. Mulligan was FANTASTIC about explaining the next steps in my health care. He answered all questions and was wonderful to talk to!

Reviewed on Aug 13, 2020

Dr. Mulligan is one of the best Dr.s I see. He is truly concerned with my health and well being. He works with me as an individual ( one that can be difficult at times ) and is willing to tailler my care. My issue is rather unique and as such takes a Dr. who will take the time to delve into which he does. At my last encounter with him, we spoke for over an hour. That and the fact that he allows me to contact him directly is a great comfort. I'm lucky to have found him.

Reviewed on Aug 12, 2020

I respect and understand Dr.Mullagan he explains everything to the fullest extent and I think that's what every Dr.should do. I have no problem with him being my Dr. he really cares about me as a person and a Patient.

Reviewed on Aug 6, 2020

Dr Mulligan was recommended to me by a friend and I will definitely do the same

Reviewed on Aug 6, 2020

Dr Mulligan took the time to answer all of my questions completely, and asked if I had any other questions or concerns. He thoroughly explained his treatment plan and asked if I agreed to it. I am very confident that Dr Mulligan will determine my needs and the next steps to take. I am very pleased with Dr Mulligan's care.

Reviewed on Aug 5, 2020

Dr Guy Mulligan is a very knowledgeable, compassionate and caring physician. I am glad I chose him to help me manage my health.

Reviewed on Jul 6, 2020

Dr Mulligan took the time to listen to my concerns and we developed a plan together. He is a wonderful doctor!

Reviewed on Jul 2, 2020

I will return to Dr Mulligan for further information & decisions for my health care. I am confident in his skills & ability.

Reviewed on Jun 12, 2020

Dr. Mulligan is outstanding.

Reviewed on Jun 9, 2020

Dr. Mulligan was excellent and listened to me.

Reviewed on Jun 5, 2020

referred Dr Mulligan to many people already

Reviewed on Jun 2, 2020

I live three hours from Dr. Mulligan so the video visit was so much more convenient. I'm glad he mentioned he plans to continue them. Although I like seeing him in person, it will help so much more to not have to take a full day off work and drive 6 hours round trip. Plus now, my friends may be more likely to utilize his services since they would not need to drive to see him!

Reviewed on May 26, 2020

Dr. Mulligan is ver patient and thorough with his analysis of the test results.

Reviewed on May 22, 2020

Dr. Guy Mulligan and my ability to access a visit with him was effortless. Thank you.

Reviewed on May 22, 2020

Dr. Guy Mulligan was professional, courteous, and concerned generally about my condition and offered the necessary/appropriate medical advise to meet my needs. I respect him very much.

Reviewed on May 21, 2020

Dr. Mulligan is extremely caring and patient. He puts me at ease, really listens to me, and always addresses my concerns. The video appt. wasn't quite as good as an actual visit, but it sufficed.

Reviewed on May 21, 2020

It was excellent all the way around. Staff and Dr. Mulligan.

Reviewed on May 21, 2020

Dr. Mulligan is excellent. I am so glad I found him and I have recommended him to others.

Reviewed on May 21, 2020

Dr. Mulligan is an excellent physician. He makes sure to answer my questions and provide useful information. I greatly value his expertise and his interpersonal style.

Reviewed on May 13, 2020

Doctor Guy Mulligan, is a good listener and is interested in my overall health. Very knowable.

Reviewed on May 8, 2020

Dr. Mulligan took the time to explain my condition in a very clear manner, and gave me actionable steps moving forward. I appreciated that he listened to my concerns and we are now addressing how to get me to optimal health. One of the best specialist visits I have had at CCF.

Reviewed on May 6, 2020

I have recommended Dr. Mulligan to my coworkers at Progressive Insurance Company and to my friends. I am from the Cleveland area, but his care is worth driving to Twinsburg!

Reviewed on May 4, 2020

extremely thorough, seemed to genuinely care and want to help me. honestly best doctor I have ever had. He addressed every complaint and explained medical terms to me with excellent detail. all around excellent doctor

Reviewed on Apr 28, 2020

Made going to the dr. Enjoyable. It is refreshing to meet with a dr. Who has conversation vs q&a on a computer

Reviewed on Apr 27, 2020

Very thoughtful doctor, kind and knowledgeable about his field.

Reviewed on Apr 1, 2020

Dr M is very good. My thanks.

Reviewed on Mar 19, 2020

Dr Mulligan spent a ton of time with me to answer my questions and share his knowledge with me! I truly appreciate him!

Reviewed on Mar 17, 2020

I have nothing but praise for Dr. Mulligan and his staff. During this rough time of the Corona Virus, they were great.

Reviewed on Mar 12, 2020

Dr Mulligan was very understanding and did not rush.

Reviewed on Mar 6, 2020

Dr. Mulligans is excellent. I have recommended him to others numerous times.

Reviewed on Mar 3, 2020

I would and have recommended Dr. Mulligan to people. Very pleased. He is caring kind and helpful and professional

Reviewed on Mar 2, 2020

awesome Doctor

Reviewed on Mar 2, 2020

Called first thing Monday morning and scheduler was able to get me an appointment with Dr. Mulligan at 2pm the same day. Amazing.

Reviewed on Mar 2, 2020

Dr. Mulligan is extremely good in explaining his thinking regarding care and treatment and involving me in the process. All doctors in the CC system are impressive, but Dr. Mulligan even stands out in this elite company.

Reviewed on Feb 27, 2020

Dr. Mulligan was very good and took the time in discussing alternative meications.

Reviewed on Feb 26, 2020

Dr. Mulligan is very respectful and thorough. He explains everything clearly. His care makes me feel like we are working together for my health.

Reviewed on Feb 20, 2020

The office visit was a very pleasant and Dr. Mullillian took the time to answer all of my questions concerning my matter.

Reviewed on Feb 19, 2020

Dr. Mulligan is a wonderful, caring Doctor

Reviewed on Feb 19, 2020

Very happy with Dr. Mulligan

Reviewed on Feb 11, 2020

very good experience. Dr. Mulligan is a good Dr.

Reviewed on Feb 11, 2020

I can't express just how grateful I am that I found Dr Mulligan. I have seen many endocrinologists and he is THE BEST. I would never travel the distance if he didn't stand out from all the rest.

Reviewed on Feb 7, 2020

Dr. Mulligan is the best

Reviewed on Feb 6, 2020

Dr. Guy Mulligan provides the most thorough evaluation and detailed explanation of any doctor I have ever known.He explains my medical tests, medication, response to intervention, and thyroid nodule monitoring plan in easy to understand language. I trust his expertise and recommendations explicitly. I will recommend Dr. Mulligan to others who need a medical professional to evaluate the whole person treatment plan and how other specialists' care is impacting the patient.

Reviewed on Feb 5, 2020

Dr. mulligan was very thorough in listening, explaining, and giving options. I very much appreciated his approach and manner.

Reviewed on Feb 5, 2020

dr. mulligan always takes the time to listen to my concerns.

Reviewed on Jan 31, 2020

All Doctors should be as kind, understanding and concerned as Dr. Mulligan.

Reviewed on Jan 29, 2020

I appreciate Dr. Mulligan for his kindness and willingness to answer my questions. If he feels I don't understand what he is saying he always does what is necessary to make sure I do understand. He treats me like a human being instead of just another patient he needs to move through Cleveland Clinic's assembly line. I believe he wants me to succeed in taking better care of myself and controlling my diabetes.

Reviewed on Jan 28, 2020

Dr. Mulligan and his entire staff are excellent... so polite, kind and attentive to me. i am so very happy with the Cleveland Clinic. The ladies in the pharmacy are the best,,, really the best. I have put in comment cards many times but never know if they are read.... the people from the front door to the blood lab are helpful and very polite, and so fast. You have the best people working at Twinsburg Cleveland Clinic.... can not say enough about them.

Reviewed on Jan 14, 2020

I waited 1hour and 40 minutes for an appointment that took 10minutes. I love Dr. M, but that was ridiculous. it would be great if patients could be informed of wait times so they can plan their day better. I missed an event at my child's school because the wait was so long.

Reviewed on Jan 14, 2020

I really love Dr. Mulligan. He is kind and caring, he listens to me and he is a genius

Reviewed on Jan 13, 2020

Dr. Mulligan listens and take his time with you.

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