DS
41 Years of Experience
Accepting patients
Affiliated with a Castle Connolly Top Hospital
Who is Dr. Shields, Gastroenterologist in San Mateo, CA?
Dr. David Shields, MD is a Gastroenterologist, who primarily practices in San Mateo, CA with 2 additional practice locations. He has been practicing for over 41 years and is board certified. Dr. Shields graduated from University of California and completed his residency at Stanford U Hosp. Dr. Shields is fluent in English and Spanish, and is currently seeing new patients. Dr. Shields’s practice accepts Medicare and other major insurance plans. To book an appointment or to confirm insurance options, please call Dr. Shields’s office at (650) 324-1020.
Where did Dr. Shields go to medical school and complete their residency?
Residency: Stanford U Hosp
Medical School: University of California
Is Dr. Shields board certified as a Gastroenterologist?
Yes, Dr. David Shields, MD is board certified by the American Board of Internal Medicine
What languages does Dr. Shields speak?
Dr. Shields and their clinical team can communicate with patients in the following languages:
English
Spanish
What conditions does a Gastroenterologist like Dr. Shields typically treat?
As a Gastroenterologist, Dr. Shields 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. Shields. 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. Learn more about our claims-based healthcare methodology.
Also known as:
- Abnormal Bowel Movements
- Bowel Movement
- Unusual stool
- Changes in poop
- Fecal changes
ICD-10 Codes:
- R195: Other fecal abnormalities
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:
- Chronic Stomach Inflammation
- Stomach Disorder
- Gastritis & Gastropathy
- Chronic gastritis
- Long-term stomach inflammation
- Persistent stomach lining inflammation
ICD-10 Codes:
- K2950: Unspecified chronic gastritis without bleeding
Also known as:
- Other Pre-Procedure Examination
- Various pre-op checks
- Miscellaneous pre-surgery exams
- Other pre-treatment assessments
ICD-10 Codes:
- Z01818: Encounter for other preprocedural examination
What procedures does a Gastroenterologist like Dr. Shields typically perform?
As a Gastroenterologist, Dr. Shields 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. Shields. 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. Learn more about our claims-based healthcare methodology.
Also known as:
- Diagnostic Colonoscopy with Biopsy
- Colonoscopy with Polyp Removal
- Colonoscopy with Biopsy
- Colonoscopy
- Colorectal Cancer Screening Tests
- Flexible Colonoscopy
- Colon Exam with Biopsy
- Lower Endoscopy
- Colon Cancer Screening
- Flexible Colonoscopy with Polypectomy
- Colon Polyp Removal
- Colorectal Lesion Excision
- Colon Biopsy
- Large Intestine Scope
- Colorectal Cancer Screening
CPT Codes:
- 45378: Colonoscopy, flexible; diagnostic, including collection of specimen(s) by brushing or washing, when performed (separate procedure)
- 45385: Colonoscopy, flexible; with removal of tumor(s), polyp(s), or other lesion(s) by snare technique
- 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
Also known as:
- Diagnostic Upper Endoscopy with Biopsy
- Upper Endoscopy with Varices Banding
- EGD with Esophageal Balloon Dilation
- EGD with Biopsy
- Esophagogastroduodenoscopy
- Upper GI Endoscopy
- Stomach Scope with Sample
- EGD with Band Ligation
- Esophageal Varices Banding
- Gastric Varices Treatment
- 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)
- 43244: Esophagogastroduodenoscopy, flexible, transoral; with band ligation of esophageal/gastric varices
- 43249: Esophagogastroduodenoscopy, flexible, transoral; with transendoscopic balloon dilation of esophagus (less than 30 mm diameter)
Also known as:
- Flexible Sigmoidoscopy
- Colorectal Cancer Screening Tests
- Sigmoidoscopy
- Lower colon exam
- Flexible colon scope
- Rectum and lower colon check
CPT Codes:
- 45330: Sigmoidoscopy, flexible; diagnostic, including collection of specimen(s) by brushing or washing, when performed (separate procedure)
Does Dr. Shields accept my insurance?
Dr. Shields accepts most major insurance plans. Important: Please call our office at (650) 324-1020 before your appointment to verify that your specific plan and network are accepted.
What insurance plans does Dr. Shields accept in San Mateo, CA?
Dr. Shields in San Mateo, CA accepts plans from many carriers. While this list is updated regularly, it is not a guarantee of coverage.
Top Insurances
All Other Third Party
Medicare
State of California
Unknown
View All Insurances
Where is Dr. Shields' office located?
What is Dr. Shields's NPI number?An National Provider Identifier (NPI) is a unique ID number that identifies doctors and healthcare providers nationwide.
Dr. Shields's National Provider Identifier (NPI) number is 1578671608.
What common questions do patients ask about Dr. Shields?
Here are answers to patients Frequently Asked Questions (FAQ’s) about Dr. Shields
What is Dr. David Shields's specialty?
Dr. Shields is a Gastroenterologist near San Mateo, CA.
What does a Gastroenterologist do?
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.
Is this Dr. David Shields affiliated with a ranked Castle Connolly Top Hospital?
Yes, Dr. Shields is affiliated with San Mateo Medical Center, San Mateo Medical Center, Stanford Health Care - Stanford Hospital, Ahmc Seton Medical Center 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
When to see a Gastroenterologist?: Guides for symptoms, conditions, and treatments
Understand your symptoms and know when it’s time to see a Gastroenterologist. Explore 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 David Shields accepting new patients in San Mateo, CA?
Yes, Dr. David Shields is accepting new patients at this time.
Does Dr. David Shields offer online booking?
Please contact Dr. Shields's office at (650) 324-1020 for information about online booking, telehealth, or to schedule an appointment.
How can I make an appointment with David Shields?
Please contact Dr. Shields's office at (650) 324-1020 for information regarding telehealth appointment availability or for scheduling assistance.
Which board certifications does Dr. David Shields have?
Dr. David Shields is certified by the American Board of Internal Medicine.
Other Gastroenterologist Near San Mateo, CA

Gastroenterologist
Dr. Joanne Imperial, MD is a Gastroenterologist, who primarily practices in Palo Alto, CA with 2 additional practice locations. She is board certified.
Palo Alto, CA
VP
Gastroenterologist
Dr. Vijay Pottathil, MD is a Gastroenterologist, who primarily practices in Belmont, CA with 2 additional practice locations. He is board certified.
Belmont, CA
SR
Gastroenterologist
Dr. Stanley Rockman, MD is a Gastroenterologist, who primarily practices in San Mateo, CA. He has been practicing for over 54 years and is board certified.
San Mateo, CA