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 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

368 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 4.8

113 Patient Comments

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

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 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

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

Reviewed on Nov 11, 2019

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

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.

Reviewed on Sep 6, 2019

Dr. Mulligan is Wonderful! Worth the drive,

Reviewed on Sep 4, 2019

dr mulligan explains every detail in a way that is understanding to me he spends a great deal of time to make sure I am taking my meds properly

Reviewed on Sep 4, 2019

dr mulligan is an excellent provider. he listens and actually cares about your answers . he doesn't try to push you out of the office and spends a great deal of time with you.

Reviewed on Sep 4, 2019

Dr. Mulligan is the most caring and concerned physician I have ever met in my life. He listens, I mean really listens when we are talking. He is focused on my "whole" person and well being, not just his area of specialty.

Reviewed on Sep 4, 2019

Dr. Mulligan is concerned about the 'whole' patient.

Reviewed on Aug 29, 2019

Dr. Mulligan is extraordinary. He listens, he explains, he cares.

Reviewed on Aug 29, 2019

Dr mulligan always fully explains plan of care

Reviewed on Aug 29, 2019

Best doctor I've ever been to!

Reviewed on Aug 20, 2019

this was one of, if not the best doctor we have ever met. Dr Guy Mulligan was very efficient, caring, courteous, professional. He provided education for diabetes. we believed that we found the best. Hope he is able to assist us with care from now on. It's a rare experience to find a health care provider like Dr Mulligan.

Reviewed on Aug 19, 2019

my time with Dr. Mulligan was most informative and respectful.

Reviewed on Jul 11, 2019

Dr. Mulligan is kindly, caring, concerned and oneof my favorites!!! He needs to be recognized forhis excellence! He is such a dedicated person.He suffered cancer as a 4 yr. old child, plus aheart transplant 5 yrs. ago! WHAT A GUY!!

Reviewed on Jul 11, 2019

I am good with any waiting, because Dr.Mulligan is very thorough with his patients.

Reviewed on Jul 10, 2019

dr. Mulligan and his staff are always wonderful I wish I would have found them years earlier.

Reviewed on Jul 10, 2019

dr. Mulligan is very thorough and I appreciate that he treats me like a person and not a number as well as his staff

Reviewed on Jul 8, 2019

Dr. Mulligan is outstanding!! I have been more than impressed with every interaction. He is thorough, knowledgeable, so helpful, quick to respond to questions or concerns via email (Which is FAR above and beyond!), kind, etc etc. I literally can't rave about him or the care I've received from him more! He has been so wonderful to work with through a difficult diagnosis and such a lifesaver with some complications throughout. I would recommend him again and again!!! very impressed and thankful to work with a physician like him.

Reviewed on Jul 8, 2019

Dr. Mulligan is a very good doctor. Showed genuine concern and empathy that I really haven't seen from a doctor before.

Reviewed on Jul 3, 2019

Dr. mulligan talked me thru procedure and put me at ease while he did the biopsy.

Reviewed on Jul 1, 2019

Dr. Mulligan is one greatest asset of the clinic, knowledgeable, caring and thoughtful. I recommend him to anybody who needs help in endocrine system.

Reviewed on Jul 1, 2019

Dr. Mulligan has a great team.

Reviewed on Jun 28, 2019

Dr. always is concerned and listens

Reviewed on Jun 27, 2019

My experience with Dr. Mulligan is always reassuring and pleasant.

Reviewed on Jun 27, 2019

I needed to pick a doctor that would address my issues, and I could not have made a better choice!

Reviewed on Jun 19, 2019

Dr. Mulligan always takes the time to explain everything to me. He's one of the best doctors I've ever had. He not only listens to you as a patient, but takes the time to answer your questions. I never feel rushed.

Reviewed on Jun 4, 2019

*Dr. Mullian takes time & cares about his patients. I imagine that's why he gets behind. Highly recommend him.

Reviewed on May 24, 2019

Doctor and his team took a long time with me on first visit. They listened and I felt very good about the treatment they suggested.

Reviewed on May 24, 2019

Dr. Mulligan was fantastic. conversation excellent. Discussed tests & thoroughly explained results of ultrasound & showed me what I needed to know. wish more Dr's were like him taking time & making you feel comfortable not rushed.

Reviewed on May 21, 2019

able to email dr Mulligan and he is very prompt responding and always available to the patient

Reviewed on May 20, 2019

Dr. Mulligan's expertise is worth the wait.

Reviewed on May 20, 2019

very nice lady. I feel bad because she had to deal with all the patients that are upset because the doctor is running so far behind. Dr Mulligan is a great doctor, but his patient load is way to high. they need to schedule less patients or have him not take on new patients. we have lives too. I left work early and could easily have finished out my day.

Reviewed on May 14, 2019

Dr. Mulligan was really wonderful! My medical situation is far from typical, and he provided caring and proficient treatment and guidance.

Reviewed on May 10, 2019

Dr. Milligan typed his summaries in my full view so i could read what he was writing. Very courteous and informative.

Reviewed on Apr 26, 2019

Dr. Mulligan is the best doctor I've ever had. He always takes time to listen to me and explains medications thoroughly.

Reviewed on Apr 16, 2019

Dr Mulligan was great. He spent time explaining my condition and answered all my questions.

Reviewed on Apr 10, 2019

I really like Dr. Mulligan. He is never in a hurry. He listens to all of my input and considers each one. Started on a new insulin and he provided a chart on dosages. He was very thorough in making sure I understood everything.

Reviewed on Apr 10, 2019

Dr.Mulligan was recommended to me by a 3rd party. Dr. was courteous and spent time with myself and husband explained everything clearly

Reviewed on Apr 10, 2019

Dr. Mulligan is one of the best doctors I have ever known. He's very knowledgeable. He listens to my concerns, gives me feedback on treatment that may or may not have worked and is just an all around nice person. I have recommend him to several people who suffer from the same affliction as I do.

Reviewed on Apr 8, 2019

simply the best Dr. I have ever had!

Reviewed on Apr 8, 2019

Dr Mulligan was thorough, caring, and kind.

Reviewed on Apr 4, 2019

Very good. Dr. Mulligan is very thorough, helpful, and informative. Always a pleasant experience.

Reviewed on Apr 4, 2019

Dr. Mulligan IS THE BEST!! What a caring,wonderful human being!

Reviewed on Mar 22, 2019

Dr. Mulligan is very good and thorough and he treats me as an individual with unique needs and not a one size fits all approach other hospitals and care givers have done.

Reviewed on Mar 14, 2019

Dr Mulligan is fantastic. if I had a question or a concern he addressed every question with a very easy to understand answer. he spent time explaining why and how we were going to address each issue.

Reviewed on Mar 11, 2019

Cannot say enough good things about Dr. Mulligan's knowledge, presentation skills, and allowing enough time to answer all my questions and explain things thoroughly to me.

Reviewed on Mar 11, 2019

I don't mind waiting because I know Dr. Mulligan is going to answer all my questions without rushing me.

Reviewed on Mar 6, 2019

Dr. Mulligan is very nice professional and extremely caring. I have recommended him to others as well. He spent time with answered my questions and concerns completely.

Reviewed on Mar 4, 2019

having dealt with insensitive endocrinologists in the past, dr. mulligan was a welcome and refreshing reprieve that eased my anxiety about this type of visit, and did not make me feel like my issues were 100% my fault. I cried several times because l was happy to feel seen and heard. he is a very kind man.

Reviewed on Feb 28, 2019

Dr. Mulligan always takes the time to listen to my concerns and makes sure that all of my questions are answered and that I understand everything discussed during my visit.

Reviewed on Feb 26, 2019

I would recommend Dr. Mulligan to anyone looking for a great Endocrinologist. he is smart smart, articulate and answers all my questions before I ask them.

Reviewed on Feb 25, 2019

Provider listened to my concerns and provided information on how to understand condition. I was given information to recon tact him if any concerns occurred in future. I would recommend provider to anyone needing similar treatment.

Reviewed on Feb 19, 2019

I haven't had any bad experiences with Dr Mulligan. He is literally THE BEST doctor I've ever seen. He looks outside the box for solutions. I hope he never leaves the Clinic!

Reviewed on Feb 19, 2019

I have recommended Dr Mulligan to several of my friends who need a good endocrinologist who actually listens to their problems and concerns. He is the best.

Reviewed on Feb 18, 2019

Dr. Mulligan is extremely thorough and compassionate. He is clear in his explainations and takes your input into account when making changes to care plans. He is the best doctor I have ever worked with.

Reviewed on Feb 14, 2019

I appreciated the time and attention Dr. Mulligan gave me to understand my diagnosis and how to manage it. I felt very comfortable moving forward.

Reviewed on Feb 13, 2019

The doctor was very compassionate and helpful

Reviewed on Feb 6, 2019

Doctor Mulligan is very thorough and answers any questions.

Reviewed on Feb 4, 2019

He is a fantastic Doctor, well worth any wait, because I know when he is with me, he is totally focused on my medical issues. I never feel rushed.

Reviewed on Feb 1, 2019

I always recommend Dr. Mulligan to people, he is an EXCELLENT doctor, who listens to his patients, and puts their wellbeing first.

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