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 11/17/2019, 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

367 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

94 Patient Comments

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

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 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 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.

Reviewed on Dec 27, 2019

Dr Mulligan was very good. My thanks!

Reviewed on Dec 13, 2019

I am very happy to have found *Dr. Mulligan. He understands my medical needs.

Reviewed on Dec 12, 2019

I have recommended Dr. Mulligan many times. He demonstrates expertise, active listening and collaborative problem solving as well as empathy. He is absolutely top in his field and bedside manner.

Reviewed on Dec 11, 2019

Dr. Listened to me. Helped with my medication great so far

Reviewed on Dec 9, 2019

I drive from Erie, PA because *Dr. Mulligan is an excellent doctor and caring person.

Reviewed on Dec 5, 2019

Dr. Mulligan is one of the best doctors I have experienced. He works through everything methodically, providing excellent explanations and gives care, thought and consideration to all questions.

Reviewed on Dec 4, 2019

I always leave with a new plan of action that helps deal with my blood sugar issues. Dr Mulligan listens, discusses and recommends new courses of action based on my described symptoms.

Reviewed on Dec 3, 2019

I always recommend Dr. Mulligan. he has always given me excellent care.

Reviewed on Nov 13, 2019

Dr. Mulligan is always friendly & takes time to explain care options. He is very thorough & review medical statuses from years before. I am in good hands.

Reviewed on Nov 13, 2019

Dr. Mulligan is very thorough with discussing all my lab results, encouraging me with improvement, explaining what norms mean. He is very kind and spends sufficieint time and answers questions in timely manner.

Reviewed on Nov 13, 2019

Dr. Mulligan is wonderful! He took his time and asked me all sorts of questions to try and get to the root of the problem. Would recommend him to anybody and everybody.

Reviewed on Nov 11, 2019

Dr. was so thorough and knowledgeable. Very Professional and showed concern for my problem.

Reviewed on Nov 11, 2019

i was very impressed with Dr.Mulligan. Im looking forward to working with him in the future.

Reviewed on Nov 1, 2019

all good. dr. Mulligan is the best

Reviewed on Oct 31, 2019

I Dr.Mulligan was very thorough in explaining my ultrasound results . o was a first time patient of his and he didn't make me feel rushed through my appointment and he listened to my concerns. very refreshing in today's healthcare.

Reviewed on Oct 29, 2019

have gone to Dr Mulligan for years and find him caring and thorough

Reviewed on Oct 21, 2019

Dr. Mulligan is very kind, compassionate and thorough. He takes the time to review the results of ultrasound and lab work. He does not make you feel rushed with questions and concerns. That is why I continue to see him. I understand why he is running late with his appointments. I wish more doctors were like him.

Reviewed on Oct 18, 2019

Doctor Mulligan always spends a lot of timing explaining my lab work. never felt rushed.

Reviewed on Oct 15, 2019

Dr. Mulligan has not just the knowledge, but isoutstandingly kind, caring and gives his all. Heis one of Cleveland Clinic's FINEST!

Reviewed on Oct 15, 2019

Very caring doctor

Reviewed on Oct 11, 2019

wait time that day was well worth it since Dr Mulligan gave good attention and feedback during the appointment

Reviewed on Oct 10, 2019

overall an excellent experience especially since this was a new doctor for my daughter

Reviewed on Oct 10, 2019

Dr. Mulligan listens and explains in terms that I understand.

Reviewed on Oct 9, 2019

A+ provider!!!

Reviewed on Oct 9, 2019

Dr. Mulligan is a real professional when I see him I always feel I am getting great care and respect.

Reviewed on Oct 9, 2019

Dr Mulligan is outstanding . He takes more time but explains everything . He is top notch

Reviewed on Oct 4, 2019

Dr. Mulligan is an amazing doctor. He always is very thorough and spends a good amount of time going over my labs and how I've been since the last time he saw me.

Reviewed on Oct 3, 2019

Dr Mulligan always treats me with respect and kindness. Always ready to answer any questions I ask. Very thorough and informative. He is also easy to contact when needed.

Reviewed on Sep 30, 2019

The entire experience was AMAZING from the visit with the doctor to the lab and imaging departments.

Reviewed on Sep 27, 2019

Dr. Mulligan is an excellent listener and is very proactive with my Type I diabetes care.

Reviewed on Sep 27, 2019

Dr.Mulligan was a kind, knowledge, empathetic and compassionate physician.

Reviewed on Sep 25, 2019

Dr. Mulligan is hands down the best provider I have at the clinic. He is attentive, listens and includes me and helps to educate me each step of the way. The clinic should mirror him and his practice as how your providers operate.

Reviewed on Sep 25, 2019

I have recommended Dr. Mulligan to many of my friends.

Reviewed on Sep 25, 2019

Dr. Mulligan adds caring into his treatment! This aspect is rare and fleeting! He truly cares about his parents and it shows!

Reviewed on Sep 24, 2019

Girl at front desk was very helpful in making decision and scheduling appointment. Dr. Mulligan was very thorough and took the necessary time to explain the circumstances and answer my questions.

Reviewed on Sep 20, 2019

slow on calling in to be connected to a physician

Reviewed on Sep 19, 2019

I have already recommended this provider to a friend who has scheduled an appointment with him.

Reviewed on Sep 16, 2019

Everything was good the doctor was a little slow but he didn't rush all my questions were answered

Reviewed on Sep 11, 2019

Dr. Mulligan and his staff are truly professional. They visit is extraordinarily communicative. Plenty of listening by Dr. Mulligan and his staff. They care about me.

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