Dr. Ronald K. Willenborg, MD | Montclair, NJ | Internist

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Dr. Ronald Willenborg has practiced internal medicine for 49 years and is affiliated with Hackensack Meridian Mountainside Medical Center. He earned his medical degree from Rutgers New Jersey Medical School and sees patients in Montclair, New Jersey. Patients on Vitals rate Dr. Willenborg 4.4 out of 5.

Overview based on verified provider data

4.4

20 Ratings
49 years of experience
11 insurance plans accepted
speaks English
Rutgers New Jersey Medical School
8 written reviews
1 specialty
7 areas of expertise
1 hospital affiliation
2 office locations
Male

Gave an accurate diagnosis
Had a good bedside manner
Spent time with me

Based on patient feedback. Read the reviews

Dr. Willenborg's Ratings and Reviews

4.4

20 Ratings with 8 written Reviews

Average Wait Time 5 Minutes

How was your appointment with
Dr. Willenborg?

Patients’ Perspective

Gave an accurate diagnosis: (14) Did WellNeeds Improvement (0)
Had a good bedside manner: (14) Did WellNeeds Improvement (0)
Spent time with me: (14) Did WellNeeds Improvement (0)
Provided follow-up after the visit: (13) Did WellNeeds Improvement (0)
Flexible scheduling: (14) Did WellNeeds Improvement (0)
Saw me in a timely manner: No Ratings
Staff was courteous: No Ratings

20 ratings & reviews

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Showing 1 to 8 of 8 reviews

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I have had the pleasure of being under Dr Willenborg’s care for 20 years. He is absolutely the best combination of professional, experience and bedside manner that anyone would want. Will miss him tremendously when he retires - Ken

Did Well

Gave an accurate diagnosis
Had a good bedside manner
Spent time with me
Provided follow-up after the visit
Flexible scheduling

Needs Improvement

November 23rd, 2019

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Went begfore and going back. Insurance changes.

Did Well

Gave an accurate diagnosis
Had a good bedside manner
Spent time with me
Provided follow-up after the visit
Flexible scheduling

Needs Improvement

January 18th, 2016

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Dr. Willenborg is a true professional and a dedicated Doctor. I give the Dr., and staff an Excellent rating.

Did Well

Gave an accurate diagnosis
Had a good bedside manner
Spent time with me
Provided follow-up after the visit
Flexible scheduling

Needs Improvement

May 15th, 2012

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Dr. Willenborg saved my life 15 years ago with an accurate diagnosis. He is always there for me when I need him.

Did Well

Gave an accurate diagnosis
Had a good bedside manner
Spent time with me
Provided follow-up after the visit
Flexible scheduling

Needs Improvement

October 22nd, 2011

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Dr. Willenborg is the best Internal Medicine doctor I have visited. He is comprehensive, accurate and caring.

Did Well

Gave an accurate diagnosis
Had a good bedside manner
Spent time with me
Provided follow-up after the visit
Flexible scheduling

Needs Improvement

March 29th, 2010

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Thorough, provides a clear and complete diagnosis, considers all options

Did Well

Gave an accurate diagnosis
Had a good bedside manner
Spent time with me
Provided follow-up after the visit
Flexible scheduling

Needs Improvement

January 25th, 2010

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Dr. Willenborg is a caring physician, extremely well trained, thorough and an outstanding diagnostician. He explains my health conditions, effectively manages them.I feel he keeps me safe from illnesses. He calls me with test results as soon as he gets them. He effectively interprets test results.Gives clear instructions.Outstanding doctor. He views the patient as a person, not only a health condition.

Did Well

Gave an accurate diagnosis
Had a good bedside manner
Spent time with me
Provided follow-up after the visit
Flexible scheduling

Needs Improvement

January 8th, 2010

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Dr. Willenborg is so fantastic that he should be in a Norman Rockwell painting. His style is that of the old time doctors that would make house calls. He is knowledgeable about every disease and is up on the current research. He spends time with you and answers all of your questions. He will call you back within minutes if you call with an emergency. He calls you personally with your test results within days. I have numerous medical issues and he effectively manages them all. He coordinates with my specialists, and follows up with them. I literally trust him with my life, and would not go to any other doctor!

Did Well

Gave an accurate diagnosis
Had a good bedside manner
Spent time with me
Flexible scheduling

Needs Improvement

December 23rd, 2008

Dr. Ronald K Willenborg

543 Valley Rd Ste 4Montclair, NJ 07043

Mon8:00 am - 5:00 pm

Tue8:00 am - 5:00 pm

Wed8:00 am - 5:00 pm

Thu8:00 am - 5:00 pm

Fri8:00 am - 5:00 pm

SatClosed

SunClosed

Dr. Ronald K Willenborg

543 Valley RdUpper Montclair, NJ 07043


Dr. Ronald K Willenborg, MD	Dr. Muhammad Reza Zakaria	Dr. Larisa V Mashensky, MD	Dr. Mukund Madhaw Das, MD
Internal Medicine	Internal Medicine	Internal Medicine	Internal Medicine
	Accepts New Patients	Accepts New Patients	Accepts New Patients
4.4 (20 Ratings)	4.7 (3 Ratings)	4 (22 Ratings)	0 (0 Ratings)
49 Years of Experience	40 Years of Experience	31 Years of Experience	10 Years of Experience
No Virtual Visit Option	No Virtual Visit Option	No Virtual Visit Option	Virtual Visit Available
Speaks English	Speaks English, Russian, Spanish	Speaks English, Russian	Speaks English, Hindi, Urdu
Montclair , NJ	Brooklyn , NY	New York , NY	Bergenfield , NJ
Med School: Rutgers New Jersey Medical School	Med School: Dhaka Medical College And Hospital	Med School: First Tashkent State Medical Institute	Med School: St Georges University School Of Medicine
Current Profile	View Profile	View Profile	View Profile

Search for your insurance and plan

Accepts Medicaid
Aetna
Blue Cross Blue Shield
Cigna
Horizon Blue Cross Blue Shield of New Jersey
Medicare
Medicare - Medicaid
Medicare - Medicare
Meritain Health
UnitedHealthcare
UnitedHealthcare - Medicare
UnitedHealthcare Oxford

Internal Medicine

Check-up
Heartburn
Immunization
Physical
Vaccination
Weight Loss
Weight Loss (non-surgical)

Dr. Ronald K Willenborg holds an inactive medical license in the state of New Jersey.

Medical License

Medical Doctor with an inactive medical license in the state of New Jersey.

Education & Training

Medical School

Graduated from Rutgers New Jersey Medical School in 1977.

NPI Number

Dr. Willenborg's NPI number is 1801897897.

Andrew Charles Bybordi
Diagnostic Radiology
7 Years Exp | NEW YORK, NY
(0)
Howard Daniel Hoffman
Nephrology
49 Years Exp | Edison, NJ
(0)
Mohamed Abdo
Emergency Medicine
39 Years Exp | Wayne, NJ
(0)
Saeed Ghandili
Nuclear Medicine
15 Years Exp | Bronx, NY
(0)
Manar Samih El-Aker
Pediatrics
30 Years Exp | Paterson, NJ
(0)
Joan Dupre Boomsma
Critical Care Medicine
43 Years Exp | Pompton Plains, NJ
(0)
Harsha Sai Dannapaneni
Anesthesiology
4 Years Exp | Houston, TX
(0)
Adam Misseldine
Diagnostic Radiology
3 Years Exp | Chicago, IL
(0)
Mila Wangpo Sherpa
Diagnostic Radiology
5 Years Exp | Brooklyn, NY
(0)
Yasmeen Tarek Elsayed
Anesthesiology
3 Years Exp | Jamaica, NY
(0)

Is Dr. Ronald Willenborg accepting new patients?: Dr. Ronald Willenborg has not indicated that they accept new patients. Contact their office through their Vitals profile to check for availability.
Does Dr. Ronald Willenborg accept my insurance?: You can see the insurance plans that Dr. Ronald Willenborg accepts on their Vitals profile.
How can I make an appointment with Dr. Ronald Willenborg?: You can find contact information for Dr. Ronald Willenborg here on Vitals.
Which hospitals is Dr. Ronald Willenborg affiliated with?: Dr. Ronald Willenborg is affiliated with Hackensack Meridian Mountainside Medical Center.
What languages does Dr. Ronald Willenborg speak?: Dr. Ronald Willenborg speaks English.

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