MJ
34 Years of Experience
Accepting patients
Affiliated with a Castle Connolly Top Hospital
Who is Dr. Johnston, Gastroenterologist in Lancaster, PA?
Dr. Mark Johnston, MD is a Gastroenterologist, who primarily practices in Lancaster, PA with 1 additional practice location. He has been practicing for over 34 years and is board certified. Dr. Johnston graduated from Drexel University College Of Medicine and completed his residency at Nat'L Naval Med Ctr, Gastroenterology; Naval Reg Med Ctr, Internal Medicine. Dr. Johnston is fluent in English and Vietnamese, and is currently seeing new patients. Dr. Johnston’s practice accepts Medicare, UnitedHealthcare and other major insurance plans. To book an appointment or to confirm insurance options, please call Dr. Johnston’s office at (717) 431-3000.
Where did Dr. Johnston go to medical school and complete their residency?
Residency: Nat'L Naval Med Ctr, Gastroenterology; Naval Reg Med Ctr, Internal Medicine
Medical School: Drexel University College Of Medicine | HAHNEMANN UNIVERSITY COLLEGE OF MEDICINE
Is Dr. Johnston board certified as a Gastroenterologist?
Yes, Dr. Mark Johnston, MD is board certified by the American Board of Internal Medicine
What languages does Dr. Johnston speak?
Dr. Johnston and their clinical team can communicate with patients in the following languages:
English
Vietnamese
What conditions does Dr. Johnston treat?
As a Gastroenterologist, Dr. Johnston 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. Johnston. 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:
- 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:
- Upper Middle Abdominal Pain
- Abdominal Pain
- Epigastric pain
- Pain below breastbone
- Upper stomach pain
ICD-10 Codes:
- R1013: Epigastric pain
Also known as:
- Colon Polyps
- Colonic Polyps
- Colorectal polyps
- Bowel polyps
- Intestinal polyps
ICD-10 Codes:
- K635: Polyp of colon
Also known as:
- Fluid in Abdomen
- Liver Disease
- Ascites
- Abdominal fluid buildup
- Peritoneal fluid
ICD-10 Codes:
- R188: Other ascites
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
Also known as:
- Ulcerative Pancolitis
- Ulcerative Colitis
- Chronic Pancolitis
- Extensive Ulcerative Colitis
- Inflammatory Bowel Disease (IBD)
ICD-10 Codes:
- K5100: Ulcerative (chronic) pancolitis without complications
What procedures does Dr. Johnston perform?
As a Gastroenterologist, Dr. Johnston 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. Johnston. 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 Biopsy
- Colonoscopy with Polyp Removal
- Diagnostic Colonoscopy with Biopsy
- Colonoscopy
- Colorectal Cancer Screening Tests
- Flexible Colonoscopy
- Colon Biopsy
- Large Intestine Scope
- Colorectal Cancer Screening
- Flexible Colonoscopy with Polypectomy
- Colon Polyp Removal
- Colorectal Lesion Excision
- Colon Exam with Biopsy
- Lower Endoscopy
- Colon Cancer Screening
CPT Codes:
- 45380: Colonoscopy, flexible; with biopsy, single or multiple
- 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)
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
Also known as:
- Diagnostic Upper Endoscopy with Biopsy
- EGD with Esophageal Balloon Dilation
- EGD with Biopsy
- Esophagogastroduodenoscopy
- Upper GI Endoscopy
- Stomach Scope with Sample
- Upper Endoscopy with Esophageal Dilation
- Flexible Esophagoscopy with Balloon
- EGD with Balloon Widening
CPT Codes:
- 43235: Esophagogastroduodenoscopy, flexible, transoral; diagnostic, including collection of specimen(s) by brushing or washing, when performed (separate procedure)
- 43249: Esophagogastroduodenoscopy, flexible, transoral; with transendoscopic balloon dilation of esophagus (less than 30 mm diameter)
Also known as:
- Esophageal Dilation (Bougie)
- Esophageal Widening
- Bougie Dilation of Esophagus
- Swallowing Tube Dilation
CPT Codes:
- 43450: Dilation of esophagus, by unguided sound or bougie, single or multiple passes
Also known as:
- Abdominal Fluid Drainage with Imaging Guidance
- Guided Abdominal Paracentesis
- Ascites Drainage with Ultrasound
- Fluid Removal from Belly
CPT Codes:
- 49083: Abdominal paracentesis (diagnostic or therapeutic); with imaging guidance
Also known as:
- Upper Endoscopy with Polyp Removal
- Upper Endoscopy with Tumor Ablation
- EGD with Polypectomy
- Esophagus, Stomach, Duodenum Scope with Removal
- Flexible Endoscopy Tumor Excision
- EGD with Ablation
- Esophagus, Stomach, Duodenum Scope with Ablation
- Flexible Endoscopy Lesion Treatment
CPT Codes:
- 43251: Esophagogastroduodenoscopy, flexible, transoral; with removal of tumor(s), polyp(s), or other lesion(s) by snare technique
- 43270: Esophagogastroduodenoscopy, flexible, transoral; with ablation of tumor(s), polyp(s), or other lesion(s) (includes pre- and post-dilation and guide wire passage, when performed)
Does Dr. Johnston accept my insurance?
Dr. Johnston accepts most major insurance plans. Important: Please call our office at (717) 431-3000 before your appointment to verify that your specific plan and network are accepted.
What insurance plans does Dr. Johnston accept in Lancaster, PA?
Dr. Johnston in Lancaster, PA accepts plans from many carriers. While this list is updated regularly, it is not a guarantee of coverage.
Top Insurances
Capital BlueCross
CVS Health (formerly Aetna)
Geisinger Health Plan
Highmark Inc.
Independence Blue Cross
Medicare
MedImpact
State of Tennessee
UnitedHealthcare
UPMC Health Plan
View All Insurances
Where is Dr. Johnston's office located?
Dr. Mark Johnston's Primary Practice
2112 Harrisburg Pike Ste 202
Lancaster, PA 17601
(717) 431-3000
What is Dr. Johnston's NPI number?An National Provider Identifier (NPI) is a unique ID number that identifies doctors and healthcare providers nationwide.
Dr. Johnston's National Provider Identifier (NPI) number is 1003898131.
What common questions do patients ask about Dr. Johnston?
Here are answers to patients Frequently Asked Questions (FAQ’s) about Dr. Johnston
What is Dr. Mark Johnston's specialty?
Dr. Johnston is a Gastroenterologist near Lancaster, PA. 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. Johnston to book an appointment today.
Is this Dr. Mark Johnston affiliated with a ranked Castle Connolly Top Hospital?
Yes, Dr. Johnston is affiliated with Penn Medicine Lancaster General Hospital, Paoli Hospital which are a Castle Connolly Top Hospitals. Castle Connolly Top Hospitals are healthcare institutions recognized for their excellence in specific medical procedures and overall patient care. They 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 Mark Johnston accepting new patients in Lancaster, PA?
Yes, Dr. Mark Johnston is accepting new patients at this time.
Does Dr. Mark Johnston offer online booking?
Please contact Dr. Johnston's office at (717) 431-3000 for information about online booking, telehealth, or to schedule an appointment.
How can I make an appointment with Mark Johnston?
Please contact Dr. Johnston's office at (717) 431-3000 for information regarding telehealth appointment availability or for scheduling assistance.
Which board certifications does Dr. Mark Johnston have?
Dr. Mark Johnston is certified by the American Board of Internal Medicine.
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