Theodore Sy, MD | Laguna Hills, CA | Gastroenterologist

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Dr. Theodore Sy treats colon polyps, hemorrhoids, and diverticular disease, and performs lower GI endoscopy, colonoscopy, and sedation as part of his gastroenterology practice. He has 23 years of experience and is affiliated with Memorialcare Saddleback Medical Center.

Dr. Sy is board-certified in internal medicine through the American Board of Internal Medicine and earned his medical degree from Northwestern University The Feinberg School of Medicine. He sees patients in Laguna Hills, California. Patients on Vitals rate Dr. Sy 4.35 out of 5.

Overview based on verified provider data

accepting new patients
4.3

20 Ratings
23 years of experience
46 insurance plans accepted
speaks English
Northwestern University The Feinberg School of Medicine
18 written reviews
1 specialty
12 areas of expertise
1 board certification
1 hospital affiliation
1 office location
Male

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

Based on patient feedback. Read the reviews

Theodore Sy's Ratings and Reviews

4.3

20 Ratings with 18 written Reviews

Average Wait Time 12 Minutes

How was your appointment with
Theodore Sy?

Patients’ Perspective

Gave an accurate diagnosis: (8) Did WellNeeds Improvement (2)
Had a good bedside manner: (8) Did WellNeeds Improvement (2)
Spent time with me: (8) Did WellNeeds Improvement (2)
Provided follow-up after the visit: (7) Did WellNeeds Improvement (2)
Flexible scheduling: (6) Did WellNeeds Improvement (2)
Saw me in a timely manner: No Ratings
Staff was courteous: No Ratings

20 ratings & reviews

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Showing 1 to 10 of 18 reviews

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Excellent listener— came up with plan together. Was clear about next steps. No condescension. Long wait to get in but worth it. Staff was friendly and helpful.

Did Well

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

Needs Improvement

March 26th, 2025

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Dr. Sy is very attentive!! Listened to all my concerns and provided ideas/suggestions!! I would highly recommend Dr. Sy!!

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

December 9th, 2024

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This is my consultation visit with Dr. Sy for a colondoscopy after 10 years . I think Dr. Sy is a phenomenal doctor. He is very thorough, polite and courteous. He provided clear This is my first visit with Dr. Sy after 10 years . I think Dr. Sy is a phenomenal doctor. He is very thorough, polite and courteous. He provided clear communication This is my first visit with Dr. Sy after 10 years . I think Dr. Sy is a phenomenal doctor. He is very thorough, polite and courteous. He provided clear communication about my care, answered questions and explained in details.

Did Well

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

Needs Improvement

June 13th, 2023

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This is my consultation for a colondoscopy procedure with Dr. Sy after 10 years . Dr. Sy had reviewed my records before he discussed his concerns. I think Dr. Sy is a phenomenal doctor. He is very thorough, polite and courteous. He provided clear communication about my care, answered questions and explained in details.

Did Well

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

Needs Improvement

March 21st, 2023

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Three years ago I had a colonoscopy with Dr. Sy. He is a very compassionate man. It was suggested that I have another colonoscopy this year. It was suggested that I had a more intense anesthesia for this next colonoscopy. Between 6-8 phone calls with this office, Angela the nurse was progressively more rude. I am not sure if it is COVID related but I feel she is sick of her job. I asked direct questions and I only received nebulous responses. I am looking for another doctor.

March 16th, 2021

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Dr. Sy is very knowledgeable and caring physician. I would recommend Dr. Sy to whoever is looking for a good GI specialist.

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

February 24th, 2021

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Dr. Sy has been my gastroenterologist for many years and I credit him and his nurse, Andrea Green with saving my life. They are two of the finest professionals I have had the pleasure to know and good fortune to be a recipient of their critical care.

April 17th, 2020

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Knowledgeable, professional, efficient, kind.

December 14th, 2019

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He listens, responds to what he hears and explains himself precisely.

August 11th, 2019

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Dr Sy took time to explain about my health concerns. I felt better after I left his office, not as worried as I came in. And nurse Andrea is sweeter than sugar. Thank you Team..

August 3rd, 2019

Theodore Sy, MD

26538 Moulton Pkwy Ste 38ELaguna Hills, CA 92653

Tel: (877) 696-3622

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


Theodore Sy, MD	Jan Seiler, APRN	Ashley Anderson, APRN	Ji Soo Choi, APRN
Gastroenterology	Gastroenterology	Gastroenterology	Gastroenterology
Accepts New Patients	Accepts New Patients	Accepts New Patients	Accepts New Patients
4.3 (20 Ratings)	0 (0 Ratings)	0 (0 Ratings)	0 (0 Ratings)
23 Years of Experience
No Virtual Visit Option	Virtual Visit Available	Virtual Visit Available	Virtual Visit Available
Speaks English	Speaks English	Speaks English	Speaks English
Laguna Hills , CA	Montgomery , AL	Sacramento , CA	Sacramento , CA
Med School: Northwestern University The Feinberg School of Medicine	Med School: Georgia State University	Med School: East Tennessee State University - Quillen College of Medicine	Med School: New York University
Current Profile	View Profile	View Profile	View Profile

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Gastroenterology

Acid Reflux Disease (Gastroesophageal Reflux / GERD)
Check-up
Constipation
Heartburn
Hepatitis C
Immunization
Irritable Bowel Syndrome (IBS)
Physical
Ulcerative Colitis
Vaccination
Weight Loss
Weight Loss (non-surgical)

Theodore Sy is board certified in Internal medicine by the American Board of Internal Medicine.

Board Certifications

Board certified in Internal medicine by the American Board of Internal Medicine.

Education & Training

Medical School

Graduated from Northwestern University The Feinberg School of Medicine in 2003.

NPI Number

Theodore Sy's NPI number is 1003865627.

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Dr. Donald William Bendig, MD
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Dr. Christopher Hong Chang, MD
Anesthesiology
35 Years Exp | Mission Viejo, CA
(1)
Dr. Joseph John Munoz, MD
Adolescent Medicine
54 Years Exp | Anaheim, CA
(1)
Denise Lynn Sherk
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Dr. Christopher Chu
Pediatrics
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What languages does Theodore Sy speak?: Theodore Sy speaks English.
Where is Theodore Sy's office located?: Theodore Sy's office is located at 26538 Moulton Pkwy Ste 38E, Laguna Hills, CA, 92653.
Is Theodore Sy accepting new patients?: Theodore Sy is accepting new patients on Vitals. View Theodore Sy's profile on Vitals to make an appointment.
Which hospitals is Theodore Sy affiliated with?: Theodore Sy is affiliated with Memorialcare Saddleback Medical Center.
Does Theodore Sy accept my insurance?: You can see the insurance plans that Theodore Sy accepts on their Vitals profile.

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