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 School - 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 11/19/2018, 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

362 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 5
Listens 5
Courtesy, Respect & Concern 5
Knows Medical History 4.9
Time Spent with Patient 5
Patient Rating of Doctor 4.9

70 Patient Comments

Reviewed on Nov 15, 2018

Dr. is thorough, knowledgeable and interested in listening and educating. One of the best Doctors I have ever been to!

Reviewed on Nov 7, 2018

Dr came in after nurse did preliminaries.

Reviewed on Nov 6, 2018

sometimes my wait to see dr mulligan is a little long once i get into the examination room. but i love my doctor he is understanding and he listens to me

Reviewed on Nov 6, 2018

Dr. Mulligan is amazing! I wish more drs were like him. He listens and he really wants for me to feel good.

Reviewed on Nov 6, 2018

I would wait as long as it takes to see Dr. Mulligan. i know he is giving the same attention to the person ahead of me and I appreciate that.

Reviewed on Nov 1, 2018

Always an excellent experience when I see Dr. Mulligan !!

Reviewed on Oct 30, 2018

Dr. Mulligan is a great doctor...never feel rushed

Reviewed on Oct 30, 2018

need more doctors like him, that is why I travel an hour to see him

Reviewed on Oct 26, 2018

Dr. Mulligan spends time with me and does not make me feels hurried or rushed. He is concerned and is knowledgeable about my medical care.

Reviewed on Oct 11, 2018

Dr. Mulligan always listens to what I have to say. I never feel rushed during an appointment and I leave knowing he listened to everything I had to say. He also explains things so I understand them and discusses every option for my care with me.

Reviewed on Oct 10, 2018

Dr. Mulligan is pleasant and always willing to discuss treatment options and timing with me. I value his expertise and approachability.

Reviewed on Oct 10, 2018

I waited about 25 minutes in the exam room to see Dr. Mulligan. This wait is not bothersome to me because he is generous with his time, conversation and discussions with me.

Reviewed on Oct 10, 2018

Dr. Mulligan is an amazing caregiver. He listens intently and always answers every question or concern that I have. He provides thorough explanations and consistent follow-up.

Reviewed on Oct 9, 2018

Despite the fact that Dr. Mulligan's office is over an hour's drive for me, his technical expertise and the level of care he provides are exceptional. He is the first doctor I have met at The Cleveland Clinic who listened to my concerns and explained a thorough treatment protocol. I would recommend him highly to anyone seeking care for hypothyroid disease.

Reviewed on Oct 2, 2018

Dr. Milligan is wonderful. He listened to all of my concerns and wanted extensive background information to inform his diagnosis and treatment. I normally am adverse to doctors, but Dr. Milligan is one I like and would recommend.

Reviewed on Sep 26, 2018

Everything went very well. I got appropriate answers to all my questions and Dr. Mulligan and his staff were very helpful. I would recommend him to anybody.

Reviewed on Sep 26, 2018

Dr Mulligan and his staff are great.

Reviewed on Sep 19, 2018

i luckily got scheduled with this provider because I called same day appointments. I had a question regarding treatments and the staff told me I could not get an appointment for another 5 months initially. I had a question that needed follow up because I became pregnant and luckily I knew to call same day appointments and luckily one was available that worked with my schedule. mychart messaging is also ineffective.

Reviewed on Sep 19, 2018

Dr mulligan is SO thorough and spent much time with me and my husband to discuss treatment. His skill and guidance are much appreciated and I feel at ease in his care.

Reviewed on Sep 18, 2018

I arrived for a 7:30 appointment. Was seen by nurse at @ 8. Doctor came in to exam room at @ 8:10. My total visit was about 50 minutes.

Reviewed on Sep 6, 2018

Dr Mulligan is a great doctor. the time it takes to get an appointment with him is worth the wait! He explains everything very thoroughly and answers every question. I like the fact that he really involves the patient in your own care and lifestyle changes.

Reviewed on Aug 30, 2018

concerning getting an appointment--Dr.Mulligan must be booked way ahead....

Reviewed on Aug 30, 2018

Dr. Mulligan gives such wonderful attention, I'mhappy to wait!!!

Reviewed on Aug 24, 2018

I mentioned to Dr. Mulligan that his approach to my problem was truly appreciated. He made the path to curing my hypothyroidism enjoyable.

Reviewed on Aug 13, 2018

My experience with Doctor Milligan was truly exceptional, as He clearly showed me the results of my ultra sound , explaining his course of treatments for me.

Reviewed on Aug 13, 2018

I have complete confidence in the ability of Dr. Mulligan to guide me along the path of health issues my Lord has presented to me.

Reviewed on Aug 13, 2018

after my experience of the thoroughness Dr. Mulligan spent during my exam listening to me descfibe my symptoms, I did not mind waiting , aware of his commitment to respecting his patients.

Reviewed on Aug 3, 2018

Dr. Mulligan and his nurse Ingrid are the best. She remembers who we are and will ask about things that helps us feel like we are important. Dr. Mulligan always is a good listener and always seems very up on new medications etc

Reviewed on Jul 26, 2018

Dr. Mulligan is an outstanding physician.He listens and has a pleasant personality. I never had the feeling I was being rushed.He seemed sincerely interested in helping me.

Reviewed on Jul 24, 2018

The doctor and nurses explain everything very clearly...

Reviewed on Jul 23, 2018

Dr. Mulligan and his staff are a joy and a pleasure to work with. I owe my continuing recovery from Hypopituitarism and secondary adrenal failure to Dr. Mulligan.

Reviewed on Jul 20, 2018

Dr. Mulligan is the BEST doctor at the Cleveland Clinic! He is the benchmark that the organization should use to define what World Class Health Care looks like.

Reviewed on Jul 20, 2018

Dr. MULLIGAN explains everything to you in a way you can understand it. very nice Dr. Never had any problem with him.

Reviewed on Jul 18, 2018

Dr Mulligan wanted my next appointment to be in 3-4 months and the first available was December 24th. I did have the option to see a practitioner, I opted to wait to see him due to the fact that we drive about an hour for these appointments.

Reviewed on Jul 18, 2018

This was my second visit with Dr Mulligan and both times I left the appointment with new knowledge and ideas about managing my disease. I do not leave the appointment overwhelmed with thoughts of how am I ever going to manage this problem.

Reviewed on Jul 17, 2018

waited 4 hours before appointment never checked in by desk after informing them I was early. then I waited almost an hour for the doctor

Reviewed on Jun 27, 2018

Dr. Mulligan is one of the best doctors I have ever worked with. He listened very directly to what i was saying and never doubted my experiences or thoughts regarding my health. He was incredibly knowledgeable and was very willing to to extra research to be able to answer some of my complex questions about some of my medications. I already recommended to several friends.

Reviewed on Jun 25, 2018

Dr. Mulligan was very kind and listened closely when I talked about my health problems. He wanted to know any and all information I could offer to aide in his treatment plan. He never interrupted me, belittled my views, or rushed me out. I want to continue to see him as my doctor.

Reviewed on Jun 21, 2018

Dr. Mulligan was very patient, caring and informative in dealing with me. He went above and beyond what most doctor's do. My experience with him was excellent.

Reviewed on Jun 20, 2018

Dr. Mulligan is very thorough and does not "rush through" my appointments.

Reviewed on Jun 15, 2018

Dr. Mulligan is professional, thorough and is a pleasure to see. Always has the patients best interest at heart. He is top notch.

Reviewed on Jun 13, 2018

Dr. Mulligan is very kind and easy to understand and was very patient and listened very well

Reviewed on Jun 12, 2018

I trust Dr Mulligan very much. I believe he is concerned about my health. CCF should work to get more doctors like him

Reviewed on Jun 5, 2018

Dr. Mulligan takes as much time as I need to speak with me, so I do not mind if he runs late on his appointments, because that means he is taking his time with his patients. He is a kind and caring physician that I have recommended to family and friends!

Reviewed on May 29, 2018

Dr. Mulligan is everything a patient desires ina physician. I would give him a RAVE REVIEW.He is GENTLE, COMPASSIONATE AND AGREAT LISTENER. HE ALWAYS GIVES METONS OF TIME IN THE OFFICE. He isTHOROUGH and looks over my recordscarefully. The reason nobody calls after myblood test, is that it is quickly listed onMY CHART. I am SO FORTUNATE TO HAVEthis fine man as my ENDOCRINOLOGIST!!!He deserves RECOGNITION!

Reviewed on May 29, 2018

Dr. Mulligan is very patient and kind!

Reviewed on May 18, 2018

Dr Mulligan is wonderful. He takes time to explain things to his patients. He is very thorough. Great bed side manner. I have referred other people to him in the past. I think very highly of Dr Mulligan!!!

Reviewed on May 9, 2018

PLease note. *Dr. William is a specialist who is VERY good at what he does; therefore, he is extremely difficult to make _____ because he is in very high demand.

Reviewed on May 8, 2018

Dr. Mulligan is a caring, knowledgeable, wonderful doctor. I have been seeing him for diabetes care for the past few years. Through his guidance and expertise my diabetes is under control and this condition has greatly improved. His staff is also friendly and helpful.

Reviewed on Apr 25, 2018

Dr. Mulligan and Gretchen are wonderful. They both are very thorough with my care. In addition, they don't make me feel like a number when I come in. I appreciate everything they do to help improve my health.

Reviewed on Apr 23, 2018

very good. doctor was nice and acted as though he genuinely cared. nice clean facility with friendly staff. we came 3 hrs away because of your reputation. thanks

Reviewed on Apr 19, 2018

great service with Dr Mullgain ..always listens and answers my questions

Reviewed on Apr 19, 2018

The staff at the reception area were very courteous!The visit with Dr. Mulligan was the best visit I've experienced in more than 2 decades. He explained my condition better than any other physician

Reviewed on Apr 17, 2018

waited 45 minutes in exam room to see Dr.

Reviewed on Apr 10, 2018

I dread calling the office Because of weight times in being on hold, but I stick with the Cleven clinic because of the staff and doctors. Dr. Mulligan was patient, informational, and he taught me a lot. I was very impressed as a new patient to him. sorry for the errors, I am talking to text and it will not let me go up to correct.

Reviewed on Apr 10, 2018


Reviewed on Apr 5, 2018

This was my first visit to see Dr. Mulligan. I had to wait 6 weeks to get an appointment which I thought was horrible! I waited 40 minutes once in the ffice for Dr. Mulligan to come into my room. BUT once Dr. Mulligan was in the room, I thought he was the most thurough endocrinologist I have ever seen! He spent time to answer ALL my questions and not once did I feel rushed. Dr. Mulligan was worth the wait!

Reviewed on Apr 5, 2018

Again. the wait time was way too long but Dr. Mulligan was worth the wait! He spend time with his patients!

Reviewed on Mar 20, 2018

I have and will continue to recommend Dr. Mulligan to friends and family. He has done a great job helping to improve my physical and mental health. I'm fortunate to have him as a health care provider!

Reviewed on Mar 9, 2018

Dr. Mulligan is an OUTSTANDING physician. I am lucky to have him as my endocrinologist. I am grateful for the amount of time he spends with me during my routine appointments, as I usually have questions and I am cautious before starting new medications, etc. I greatly appreciate his interpersonal and communication style.

Reviewed on Mar 7, 2018

excellent experience. Again I feel fortunate to have found this Dr. and his staff. They have the ability to make me feel comfortable discussing my disease and asking and answering all questions. it's as though I have known them as friends for years after only 2 visits. Very happy!

Reviewed on Feb 21, 2018

EXCEPTIONAL - I'm prepared and in process of moving off of two other systems (Summa, Crystal Clinic) and migrating ALL care to you - On just this one meeting (and the followup) I'm prepared to abandon decades of relationships with other providers - the Clinic should be honored to have Dr. Mulligan.

Reviewed on Feb 15, 2018

dr Mulligan is wonderful. he listens, explains things, shares medical records on computer screen, and is compassionate didn't rush through anything!!!

Reviewed on Feb 12, 2018

I appreciated the time and attention the doctor gave to me and my condition. I left feeling I was in very good hands and understanding my options completely.

Reviewed on Feb 9, 2018

Dr. Mulligan very carefully created a treatment plan for me with my input.

Reviewed on Feb 7, 2018

Dr. Mulligan was very helpful and looked up the medication on the internet for me and what Pharmacy I could get it.

Reviewed on Jan 30, 2018

Another reason why I love Dr. Mulligan is because he allows me to make decisions in my treatment. He is open to my suggestions, questions and concerns. He always has me schedule a 6 month check up, as well as, standing orders for blood test.

Reviewed on Jan 4, 2018

Dr. Mulligan was great and I even made a follow up appointment with him instead of who I was previously seeing.

Reviewed on Dec 11, 2017

My insurance is no longer covering my regular medication. Dr. Mulligan took a good deal of time to explain alternatives and options. Even directing me to coupons for my medication if my insurance gave me problems.

Reviewed on Dec 11, 2017

I do miss Dr. Mulligan having his own staff assistants/check out area.

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