JH
34 Years of Experience
Accepting patients
Who is Dr. Hahn, Gastroenterologist in Union, NJ?
Dr. John Hahn, MD is a Gastroenterologist, who primarily practices in Union, NJ with 2 additional practice locations. He has been practicing for over 34 years and is board certified. Dr. Hahn graduated from Rutgers and completed his residency at Umdnj-Univ Hosp, Internal Medicine. Dr. Hahn is fluent in English, Korean, and Spanish, and is currently seeing new patients. Dr. Hahn’s practice accepts Medicare, UnitedHealthcare and other major insurance plans. To book an appointment or to confirm insurance options, please call Dr. Hahn’s office.
What are Areas of Expertise for Dr. Hahn?
Dr. John Hahn, MD is a highly-rated, board-certified Gastroenterologist known for expertly diagnosing, treating, and managing a wide array of related conditions or procedures. Utilizing the latest medical advancements and evidence-based practices, Dr. Hahn empowers patients to confidently navigate their health journey, specializing in Colonoscopy, Peptic Acid Disorders, or comprehensive wellness support. Serving the Union/NJ community, Dr. Hahn is dedicated to enhancing lives through expert, patient-centered care.
Where did Dr. Hahn go to medical school and complete their residency?
Residency: Umdnj-Univ Hosp, Internal Medicine | UMDNJ
Medical School: Umdnj-New Jersey Med Sch- Newark Nj | Rutgers
Is Dr. Hahn board certified as a Gastroenterologist?
Yes, Dr. John Hahn, MD is board certified by the American Board of Internal Medicine
What languages does Dr. Hahn speak?
Dr. Hahn and their clinical team can communicate with patients in the following languages:
English
Korean
Spanish
What conditions does Dr. Hahn treat?
As a Gastroenterologist, Dr. Hahn diagnoses, treats, and manages a wide range of conditions. This condition information is derived from anonymized insurance claims and highlights the medical conditions most commonly treated by Dr. Hahn. It provides insight into the doctor’s areas of experience and expertise based on real-world patient encounters from the past two years, updated quarterly.
Also known as:
- Colon Cancer Screening
- Health Screening
- Colorectal Cancer Screening (PDQ®)
- Screening Tests to Detect Colorectal Cancer and Polyps
- Tests to Detect Colorectal Cancer and Polyps
- Colorectal Cancer Screening
- Colonoscopy Screening
- Bowel Cancer Screening
ICD-10 Codes:
- Z1211: Encounter for screening for malignant neoplasm of colon
Also known as:
- Colon Polyps
- Colonic Polyps
- Colorectal Polyps
- Intestinal Polyps
- Bowel Polyps
ICD-10 Codes:
- Z86010: Personal history of colon polyps
- Z860109: Personal history of other colon polyps
Also known as:
- Acid Reflux
- GERD
- Acid Reflux (GER & GERD) in Adults
- Acid Reflux (GER & GERD) in Children
- Acid Reflux (GER & GERD) in Infants
- Gastroesophageal Reflux
- Heartburn
- Indigestion
ICD-10 Codes:
- K219: Gastro-esophageal reflux disease without esophagitis
Also known as:
- Stomach Inflammation
- Stomach Disorder
- Gastritis & Gastropathy
- Gastritis
- Inflamed stomach lining
- Stomach lining inflammation
ICD-10 Codes:
- K2970: Gastritis, unspecified, without bleeding
Also known as:
- Upper Middle Abdominal Pain
- Abdominal Pain
- Epigastric pain
- Pain below breastbone
- Upper stomach pain
ICD-10 Codes:
- R1013: Epigastric pain
Also known as:
- Rectal Bleeding
- Gastrointestinal Bleeding
- Gastrointestinal (GI) Bleeding
- Anal Bleeding
- Blood in Stool
- Lower GI Bleed
ICD-10 Codes:
- K625: Hemorrhage of anus and rectum
What procedures does Dr. Hahn perform?
As a Gastroenterologist, Dr. Hahn performs a variety of medical procedures. This procedure information is derived from anonymized insurance claims and highlights the medical procedures most commonly performed by Dr. Hahn. It provides insight into the doctor’s areas of experience and expertise based on real-world patient encounters from the past two years, updated quarterly.
Also known as:
- Colonoscopy with Polyp Removal
- Diagnostic Colonoscopy with Biopsy
- Colonoscopy with Biopsy
- Colonoscopy
- Colorectal Cancer Screening Tests
- Flexible Colonoscopy with Polypectomy
- Colon Polyp Removal
- Colorectal Lesion Excision
- Flexible Colonoscopy
- Colon Exam with Biopsy
- Lower Endoscopy
- Colon Cancer Screening
- Colon Biopsy
- Large Intestine Scope
- Colorectal Cancer Screening
CPT Codes:
- 45385: Colonoscopy, flexible; with removal of tumor(s), polyp(s), or other lesion(s) by snare technique
- 45378: Colonoscopy, flexible; diagnostic, including collection of specimen(s) by brushing or washing, when performed (separate procedure)
- 45380: Colonoscopy, flexible; with biopsy, single or multiple
Also known as:
- Upper Endoscopy with Biopsy
- Biopsy
- Endoscopy
- EGD with Biopsy
- Gastroscopy with Biopsy
- Esophagogastroduodenoscopy with Biopsy
CPT Codes:
- 43239: Esophagogastroduodenoscopy, flexible, transoral; with biopsy, single or multiple
Does Dr. Hahn accept my insurance?
Dr. Hahn accepts most major insurance plans. Important: Please call our office at before your appointment to verify that your specific plan and network are accepted.
What insurance plans does Dr. Hahn accept in Union, NJ?
Dr. Hahn in Union, NJ accepts plans from many carriers. While this list is updated regularly, it is not a guarantee of coverage.
Top Insurances
All Other Third Party
Alliance 4 Health Net
Carepoint Health
Continental Benefits
CVS Health (formerly Aetna)
Express Scripts
Horizon BlueCross BlueShield
Medicare
State of Tennessee
UnitedHealthcare
View All Insurances
Where is Dr. Hahn's office located?
What is Dr. Hahn's NPI number?An National Provider Identifier (NPI) is a unique ID number that identifies doctors and healthcare providers nationwide.
Dr. Hahn's National Provider Identifier (NPI) number is 1538272091.
What common questions do patients ask about Dr. Hahn?
Here are answers to patients Frequently Asked Questions (FAQ’s) about Dr. Hahn
What is Dr. John Hahn's specialty?
Dr. Hahn is a Gastroenterologist near Union, NJ. An internist focused on diagnosing and treating disorders of the digestive system, encompassing the stomach, intestines, liver, and gallbladder. This specialist manages conditions like abdominal pain, ulcers, diarrhea, cancer, and jaundice, and performs intricate diagnostic and therapeutic procedures using endoscopes to examine internal organs. Contact Dr. Hahn to book an appointment today.
Is this Dr. John Hahn affiliated with a ranked Castle Connolly Top Hospital?
No, Hahn is not affiliated with a Castle Connolly Top Hospital, but is affiliated with the following hospitals: Bayonne Medical Center. Castle Connolly Top Hospitals are identified through a rigorous peer nomination process, evaluating factors like patient outcomes, quality of care, and expertise. The list recognizes hospitals that excel in 20 or more specific medical procedures, representing the top 25% nationwide. Castle Connolly Top Hospitals
Where can I learn more about Gastroenterologist?
Explore Gastroenterologist with insights from trusted medical experts on EverydayHealth.com, where you'll find the most relevant content and helpful condition guides for up-to date information about symptoms, causes, diagnosis, treatment and more. See all our health guides to find trusted information on medical conditions from our experts at Everyday Health.
Is John Hahn accepting new patients in Union, NJ?
Yes, Dr. John Hahn is accepting new patients at this time.
Does Dr. John Hahn offer online booking?
Please contact Dr. Hahn's office for information about online booking, telehealth, or to schedule an appointment.
How can I make an appointment with John Hahn?
Please contact Dr. Hahn's office for information regarding telehealth appointment availability or for scheduling assistance.
Which board certifications does Dr. John Hahn have?
Dr. John Hahn is certified by the American Board of Internal Medicine.
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