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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
  • 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 - 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 10/24/2021, 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

349 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

102 Patient Comments

Reviewed on Sep 17, 2021

Dr. Mulligan was very thorough and eased my concerns by explaining everything clearly. He did split screens of images so I could see last years' results compared to this years' and he also explained clearly what I was looking at on the screen to make sure I understood. I had some concerns that he explained and answered all questions with care and concern and did not make me feel rushed through appointment.

Reviewed on Sep 3, 2021

I have been very pleased with Dr. Milligan. He is a very good listener and provides numerous recommendations in regards to my condition & how I can make adjustments. Yes, I would highly recommend Dr. Milligan.

Reviewed on Aug 26, 2021

Dr Mulligan is a very good doctor who takes time with me and will talk with me. I never feel rushed.

Reviewed on Aug 19, 2021

Dr. Mulligan is a Excellent and Very Patient Dr.I'm Very Glad to have found a Very Caring Dr.

Reviewed on Aug 18, 2021

Excellent interactions with provider

Reviewed on Aug 17, 2021

Dr Mulligan and Nurse Angela are excellent healthcare professionals. Dr Mulligan is a great listener and explained information on our level. He takes all the time to answer our questions. We highly recommend him and his staff.

Reviewed on Aug 17, 2021

By far, the best doctor I have ever worked with. An excellent listener who takes his time and really gets to know your medical situation.

Reviewed on Aug 4, 2021

Dr Mulligan is great! So personable, concerned & informed. I would recommend him to any of My family. He has really helped me.

Reviewed on Jul 29, 2021

Dr. Mulligan was very empathic and thorough In his explanations to my many questions and concerns.

Reviewed on Jul 29, 2021

I always recommend Dr Mulligan to my friends! 5 isn't a high enough rating! I've spent 20 years with endocrine issues and have had several drs. He is the first Dr who listened to me and have achieved results with my treatment! I'll never have another endocrinologist!

Reviewed on Jul 26, 2021

Really a good listener! I talked too much but he listened. Nice doctor. Very happy.

Reviewed on Jul 22, 2021

Dr. Milligan is very caring and answers all my questions.

Reviewed on Jul 20, 2021

I appreciate Dr. Mulligan's listening and answering questions specific to my concerns.

Reviewed on Jul 16, 2021

Dr. Mulligan is a very good listener, shows compassion and understands my needs very well. He explains everything and gives me options. I have already recommended him to people.

Reviewed on Jul 15, 2021

Best Dr. I have seen in a long time!

Reviewed on Jul 14, 2021

Very informative visit. Dr. Mulligan is very easy to talk to. Spent more than adequate time answering my questions and doing the examination.

Reviewed on Jul 14, 2021

Dr. Mulligan Really listened to me regarding my many health problems, and helped very much to teach me to make changes that could help. I really appreciated the concern he had and the ability he had to teach me and explain things. Dr. Mulligan is an EXCELLENT Doctor,

Reviewed on Jul 12, 2021

I have recommended Dr. Mulligan to several folks.

Reviewed on Jul 12, 2021

I would recommend Dr. Mulligan to all my family and friends.

Reviewed on Jul 9, 2021

Dr. Mulligan is excellent!

Reviewed on Jul 8, 2021

Dr Mulligan very kind and explained this new,worrisome concern to both me and my husband

Reviewed on Jul 8, 2021

Good experience,just wish I didn't have to wait 19 days for fine needle aspiration biopsy. More time to worry although Dr reassured me it's okay to wait up to a month.

Reviewed on Jul 6, 2021

My best doctor! I wish all could be like him!

Reviewed on Jul 2, 2021

Dr. Mulligan is very caring, professional and knowledgeable. He does a great job explaining treatment options.

Reviewed on Jul 1, 2021

Dr Mulligan is a wonderful doctor who listens to your concerns and addresses them

Reviewed on Jun 29, 2021

Appointment was right on time no waiting long. Staff was very polite to me. Doctor visit was very good first time see this doctor and was very impressed with him.

Reviewed on Jun 9, 2021

Very good DOCTOR, He listens to the patient, and responses in language that is understood, he is an excellent doctor, he is the best.

Reviewed on May 27, 2021

Dr Mulligan is a very intelligent and thorough physician

Reviewed on May 27, 2021

At the time of my visit, my doctor was extremely patience with me, did not come across as if he only had a few minutes to discuss the reason I was there to see him. First time seeing him, he listen to me made me feel comfortable and I would recommend him to any one with the issue I went in to see him for.

Reviewed on May 26, 2021

this was my first visit with Dr mulligan. wow. he is a great doctor. I am very happy to have found him.

Reviewed on May 26, 2021

Dr Mulligan is great

Reviewed on May 25, 2021

Check in was very easy and smooth at kiosk and Dr. Mulligan is a very kind and considerate person. He'll spend as much time with you as needed until there's a clear cut plan/expectation moving forward. Wonderful Doctor!

Reviewed on May 25, 2021

Dr Mulligan is always a good listener and very attentive to my medical concerns.

Reviewed on May 21, 2021

I have never met Dr. Mulligan in person (due to COVID-19) but I'm eager to meet him. I have a VERY POSITIVE opinion of him: professionally, personally, medically, etc. Thus far, I'm really glad that he is my new endocrinologist. (My last one...of 30 years...retired.)

Reviewed on May 18, 2021

Dr Guy Mulligan is always very professional. Explains my lab work and medication in a helpful matter. always on time.

Reviewed on May 18, 2021

Love the caring doctors like Dr Guy Miulligam.

Reviewed on May 17, 2021

Dr. Mulligan is very respectful, answered all of my questions, and spent a good deal of time explaining my condition to me. I felt he listened and asked numerous questions to help me improve my overall health.

Reviewed on May 17, 2021

I only spoke with Dr. Mulligan, no other staff. I would highly recommend this service to anyone. HUGE TIME SAVER! In person is ALWAYS a MUCH longer wait in general. These tele appointments have always started on time, they are comprehensive & thorough, and no travel time involved. I believe people will take better care of themselves when they don't have to take a half of a day off to go to the doctors. ( in general ) This was my first appointment with Dr. Mulligan & I am in no way saying his office runs chronically behind, but many doctors offices do. This is a very nice service and I hope it will continue regardless.

Reviewed on May 13, 2021

I have never had a doctor listen and involve me in my care decisions like Dr. Mulligan. He is truly one of a kind.

Reviewed on May 11, 2021

Dr Mulligan is a very caring, personable, thorough provider! I feel all of my concerns are heard and addressed. I feel so blessed to have such a great provider! Thanks Cleveland Clinic!

Reviewed on May 11, 2021

Dr.Mulligan is incredibly knowledgeable and explains my disease in terms I can understand and relate to, which makes compliance to the plan of care easier.

Reviewed on May 11, 2021

Dr. Mulligan is excellent.

Reviewed on May 6, 2021

Dr Mulligan is the best

Reviewed on May 5, 2021

I receive excellent service from Dr. Guy Milligan!

Reviewed on May 5, 2021

I have recommended Dr Milligan to 3 people, who now travel 40 minutes or more for an appointment.

Reviewed on May 4, 2021

Dr. Mulligan is a very effective provider and his staff is always courteous.

Reviewed on May 4, 2021

I am always very pleased with my interactions with Dr. Mulligan and this visit was no exception.

Reviewed on Apr 16, 2021

Dr. Mulligan was one of the first doctors in a while who really slowed down for me to answer my questions. I am super thankful that I was referred to him and had the opportunity to receive care from him.

Reviewed on Apr 15, 2021

It is nearly impossible to schedule with Dr. Mulligan. He is a wonderful doctor so I don't want to find someone new. I have been seeing him for years.

Reviewed on Apr 15, 2021

love Dr. Mulligan. He explains any concerns and answers questions.

Reviewed on Apr 14, 2021

Dr Mulligan always takes the extra step to explain and answer questions

Reviewed on Apr 13, 2021

Dr. Mulligan is outstanding. He gave me clear, thorough information about my health and treatment.

Reviewed on Apr 12, 2021

Dr. Mulligan listens to what I have to say and works with me in all aspects of the care he prescribes

Reviewed on Apr 12, 2021

I have recommended Dr. Mulligan to others I know.

Reviewed on Apr 6, 2021

Dr. Mulligan is an excellent provider and always is concerned with my ongoing care. He's a great listener!

Reviewed on Mar 24, 2021

I've been very happy with my care and Dr. Mulligan is excellent at making sure I'm not well-informed and heard.

Reviewed on Mar 16, 2021

wonderful doctor with a great bedside manner

Reviewed on Feb 25, 2021

Really like Dr. Mulligan

Reviewed on Feb 25, 2021

Dr. Mulligan has always been very good at knowing my past and helping with future treatment

Reviewed on Feb 24, 2021

Dr. Mulligan was very compassionate, understanding and listened to my concerns. He was informative and I felt very much included in the decision-making process. I traveled an hour to see him and it was very much worth my time. I would definitely recommend him!

Reviewed on Feb 15, 2021

Dr. Mulligan was very caring and very professional. He answered all of my questions, including one that I sent to him through my chart a couple of days after the video appointment .

Reviewed on Feb 15, 2021

I appreciated the opportunity to be able to meet with Dr. Mulligan virtually, as I am trying to avoid going places and doing things in-person until I am able to be fully vaccinated. I also appreciated the convenience of being able to meet with Dr. Mulligan in the comforts of my own home, especially on a cold day.

Reviewed on Feb 12, 2021

Great Doctor!

Reviewed on Feb 1, 2021

Dr. Mulligan has always listened to my concerns and offered helpful advice. I have already referred a friend to him.

Reviewed on Jan 7, 2021

Dr Mulligan is great and you can tell he has a genuine concern for me.

Reviewed on Jan 4, 2021

Dr Mulligan is a very good doctor. I would highly recommend him!

Reviewed on Dec 24, 2020

I would like to give a rating higher than 5 to Dr. Mulligan. he was beyond excellent. the best doctor I have ever experienced in my 60 years of visiting doctors. he was very pleasant and thorough. He took time with me and he listened well. He educated me about my health. He did not rush me. Most doctors seem to rush me through the appointment. They don't like a lot of questions as it slows them down. But patients need the time and commitment from their doctor. it's our health we're dealing with.

Reviewed on Dec 23, 2020

Dr Mulligan explained the biopsy procedure and what to expect thoroughly beforehand, and also answered all of my questions. During the procedure Dr Mulligan checked in with me step by step to determine how I was feeling and describe what would occur next. I felt very calm.

Reviewed on Dec 18, 2020

so very pleased with the care and concerns of Dr Mulligan

Reviewed on Dec 18, 2020

both my primary and dr mulligan have consulted as together giving me a positive as to my health issues

Reviewed on Dec 17, 2020

I was very satisfied and impressed with Dr. Guy B Mulligan. He took the time to explain fully my situation and course of action. He listened carefully of my concerns and advised me on the implications to my satisfaction. I would recommend Dr. Mulligan.

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 7, 2020

Dr. Mulligan was caring, attentive, respectful and compassionate. He was complimentary and encouraging. He made me want to take better care of myself. I have not had this experience with other Cleveland Clinic providers. I have recently been very disappointed with several and have had less than good experiences.

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

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