Dr. Ronald K. Willenborg, MD | Montclair, NJ | Internal Medicine

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Dr. Ronald Willenborg is an internal medicine physician who graduated from Rutgers New Jersey Medical School. With nearly five decades of medical practice, he has built extensive expertise in treating adult patients with a wide range of health conditions. Dr. Willenborg speaks English and has dedicated his career to comprehensive internal medicine care.

Dr. Willenborg practices at Hackensack Meridian Mountainside Medical Center and sees patients in Montclair, New Jersey. He specializes in treating allergies and allergic reactions, including seasonal rhinitis that affects many patients during certain times of the year. His practice offers allergen immunotherapy and sublingual immunotherapy to help patients build tolerance to specific allergens. Patients have given him an average rating of 4.4 out of 5 stars on Vitals, reflecting their confidence in his care.

AI-generated from data on this provider profile.

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 board certification
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

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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

November 23rd, 2019

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Went begfore and going back. Insurance changes.

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.

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.

October 22nd, 2011

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

March 29th, 2010

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

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.

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!

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. Mohini Aras, MD	Dr. Blanca M Sckell, MD	Dr. Laurence Lamie Rezkalla, MD
Internal Medicine	Internal Medicine	Internal Medicine	Internal Medicine
		Accepts New Patients
4.4 (20 Ratings)	5 (11 Ratings)	5 (2 Ratings)	5 (4 Ratings)
49 Years of Experience	14 Years of Experience	42 Years of Experience	44 Years of Experience
No Virtual Visit Option	Virtual Visit Available	Virtual Visit Available	No Virtual Visit Option
Speaks English	Speaks English	Speaks Spanish, Chinese, English	Speaks English
Montclair , NJ	New York , NY	Flushing , NY	Brooklyn , NY
Med School: Rutgers New Jersey Medical School	Med School: Suny Downstate Medical Center College Of Medicine	Med School: Universidad Nacional De Asuncion	Med School: Assiut University
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)

MEDICAL LICENSE

Medical Doctor, New Jersey, Inactive

EDUCATION & TRAINING

Medical School

Rutgers New Jersey Medical SchoolGraduated in 1977

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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.
What languages does Dr. Ronald Willenborg speak?: Dr. Ronald Willenborg speaks English.
Which hospitals is Dr. Ronald Willenborg affiliated with?: Dr. Ronald Willenborg is affiliated with Hackensack Meridian Mountainside Medical Center.
Where is Dr. Ronald Willenborg's office located?: Dr. Ronald Willenborg's office is located at 543 Valley Rd Ste 4, Montclair, NJ, 07043.

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