Dr. Mark C. Johnson, MD | Mason City, IA | Endocrinologist

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Dr. Mark Johnson specializes in endocrinology, diabetes and metabolism, with additional expertise in internal medicine and hospice and palliative medicine. He earned his medical degree from the University of Iowa and completed his residency at the University of Nebraska Medical Center. With 49 years of medical experience, Dr. Johnson brings extensive knowledge to his practice. He is fluent in both Spanish and English.

Dr. Johnson practices at MercyOne North Iowa Medical Center and MercyOne North Iowa Acute Rehabilitation in Mason City, Iowa. He focuses on treating conditions such as high blood sugar in children, hyperglycemia, and hyperglycemic emergencies. His expertise includes performing continuous glucose monitoring and electrocardiograms to help diagnose and manage his patients' conditions. Patients have given him an average rating of 4.5 stars.

Overview based on verified provider data

accepting new patients
4.5

17 Ratings
49 years of experience
speaks Spanish, English
University Of Nebraska Medical Center
8 written reviews
3 specialties
9 areas of expertise
3 board certifications
2 hospital affiliations
2 office locations
Male

17 ratings & reviews

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Showing 1 to 8 of 8 reviews

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Dr. Johnson truly cares about the patients. He works with my other Dr.’s to coordinate my care. I am never rushed and he answers all of my questions.

January 15th, 2019

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Dr. Johnson was my doctor for appx.15 years. But when he switched to seeing only diabetic patients, I had to find another doctor as I did not have diabetes. He is the only doctor I have ever had that would actually hug you. He even called me at home 2 different times, once when I had been in a car accident and once when I had been air lifted to Iowa City with MRSA. He was very concerned about how I was doing. He is an incredibly caring doctor & person. He may sometimes have to show some "tough love" to make sure you receive the best treatment possible, but if you work with him and get through whatever you may not see eye to eye on, believe me, one day, you both will be laughing about it. So don't let the negative comments on here sway you one bit. As for the comment that he was to big for his britches; remember, Dr. Johnson does not need you as his patient, he WANTS you as his patient. And if you are lucky enough to have him as your doctor, well, what can I say except that you are a… lucky person!

August 11th, 2014

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Dr Johnson is the best in the state. He may seem 'full of himself ' but he has worked together with our community to fulfill the needs of citizens with endrinecology needs. He is purely devoted with his patients and his community. We are very lucky to have him here.

October 8th, 2013

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The only issue I have with this office is the reception desk. The younger lady is alway kind, nice and willing to help me. The old one has never been kind and always makes me feel like I'm an imposition. She shouldn't be working with patients. She would be best served working with paper and not people. I know several others who don't care for her either and one has not come back to this office because of her.

March 30th, 2012

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Dr. Johnson is a very caring physican. His office staff is not as nice as they could be, but he is worth the wait.

May 19th, 2011

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I'd went to the same endocrinologist for the past 11 years and wasn't having any luck getting my blood sugars down (I have an insulin pump). Since going to Dr. Johnson and this center my blood sugars and a1c's have NEVER been better. They take the time to help me with my pump questions and are great about calling me to follow up with any changes they had made. I do have one complaint - one of the receptionists is incredibly rude and makes faces when she's on the phone with patients so I can only imagine what she does when I call in with a question or for an appointment.

July 3rd, 2010

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He has gotten too big for his britches.

March 7th, 2010

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Not courteous

June 28th, 2009

Mercyone North Iowa Diabetes Endocrinology And Weight Loss

910 N Eisenhower AveMason City, IA 50401

Tel: (641) 428-7799

Mon7:30 am - 4:30 pm

Tue7:30 am - 4:30 pm

Wed7:30 am - 4:30 pm

Thu7:30 am - 4:30 pm

Fri7:30 am - 12:00 pm

SatClosed

SunClosed

Mercyone North Iowa Medical Center

1000 4th St SwMason City, IA 50401

Tel: (641) 428-7000


Dr. Mark Carl Johnson, MD	Dr. Jashan Gill	Dr. Umer Mukhtar	Dr. Jacob Ludwig Obholz
Endocrinology, Diabetes & Metabolism	Cardiovascular Disease	Internal Medicine	Cardiovascular Disease
Accepts New Patients	Accepts New Patients
4.5 (17 Ratings)	0 (0 Ratings)	0 (0 Ratings)	0 (0 Ratings)
49 Years of Experience	8 Years of Experience	15 Years of Experience	6 Years of Experience
No Virtual Visit Option	No Virtual Visit Option	No Virtual Visit Option	No Virtual Visit Option
Speaks Spanish, English
Mason City , IA	Mason City , IA	Mason City , IA	Marshfield , WI
Med School: University Of Iowa	Med School: Poznan Univ Of Medical Sciences Center For Medical Education In English	Med School: King Edward Medical University	Med School: Des Moines University College Of Osteopathic Medicine
Current Profile	View Profile	View Profile	View Profile

Search for your insurance and plan

Accepts Medicare
Accepts Medicaid

Check-up
Diabetes
Heartburn
Hospice & Palliative Medicine
Immunization
Internal Medicine
Physical
Vaccination
Weight Loss

MEDICAL LICENSE

Medical Doctor, Iowa, 2025, Expired

EDUCATION & TRAINING

Residency

University Of Nebraska Medical Center

Medical School

University Of IowaGraduated in 1977

Dr. Douglas Tom Summerfield, MD
Public Health & General Preventive Medicine
20 Years Exp | Mason City, IA
(0)
Dr. John Blaise Pflugi, DO
Critical Care Medicine
| Mason City, IA
(0)
Dr. Maureen Akwi Muke, MD
Hospital Medicine
14 Years Exp | Clinton, MD
(1)
Dr. Ala Mustafa
Internal Medicine
8 Years Exp | Mason City, IA
(0)
Dr. Adam Hoffmann
Internal Medicine
| Mason City, IA
(0)
Dr. Arthur Emerson McMahon Jr, MD
Internal Medicine
102 Years Exp | Mason City, IA
(0)
Dr. Keenan Leander Larsen
Internal Medicine
6 Years Exp | Wright Patterson Afb, OH
(0)
Dr. Hersi Cabdi Moallin
Internal Medicine
12 Years Exp | Mason City, IA
(0)
Dr. Nico-Al Paolo Gotera
Internal Medicine
| San Antonio, TX
(0)
Dr. Omar Yacob
Cardiovascular Disease
10 Years Exp | Mason City, IA
(0)

Which hospitals is Dr. Mark Johnson affiliated with?: Dr. Mark Johnson is affiliated with Mercyone North Iowa Medical Center and MERCYONE NORTH IOWA ACUTE REHABILITATION.
Does Dr. Mark Johnson accept my insurance?: You can see the insurance plans that Dr. Mark Johnson accepts on their Vitals profile.
How can I make an appointment with Dr. Mark Johnson?: You can find contact information for Dr. Mark Johnson here on Vitals.
Does Dr. Mark Johnson accept virtual/telehealth appointments?: Dr. Mark Johnson has not indicated that they accept virtual/teleheatlh appointments. Contact their office through their Vitals profile to check for availability.
Is Dr. Mark Johnson accepting new patients?: Dr. Mark Johnson is accepting new patients on Vitals. View Dr. Mark Johnson's profile on Vitals to make an appointment.

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