Contact Us
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Specialists in Gastroenterology
11525 Olde Cabin Road
St. Louis, MO 63141
Phone: 314-997-0554
Fax: 314-997-5086
Office Hours:
Monday - Friday
9:00 AM - 4:45 PM

Janet Todorczuk, M.D., Caroline Chang, MMS, PA-C, Erik Thyssen, M.D., Carrie Meyer, MS PA-C, Leonard Weinstock, M.D., Aman Singh, M.D., Steven Fern, D.O.,
View our frequently asked questions.
Pre-registration Telephone Numbers
Call one day before the procedure
- Advanced Endoscopy Center, call: 314-400-9999.
- Barnes-Jewish Hospital, call: 314-362-1173 or 1-800-292-3648.
- Barnes-Jewish West County Hospital, call: 314-996-8412.
- Missouri Baptist Medical Center, call: 314-996-5152.
Providers:
- Dr. Thyssen
To contact Dr. Thyssen, please call the office (314-997-0554) during regular business hours or the exchange (314-388-6578) after hours. You may also use NextMD if this is not an emergency.
- Dr. Todorczuk
To contact Dr. Todorczuk, please call the office (314-997-0554) during regular business hours or the exchange (314-388-6578) after hours. You may also use NextMD if this is not an emergency.
- Dr. Weinstock
To contact Dr. Weinstock, please call the office (314-997-0554) during regular business hours or the exchange (314-388-6578) after hours. You may also use NextMD if this is not an emergency.
- Dr. Fern
To contact Dr. Fern, please call the office (314-997-0554) during regular business hours or the exchange (314-388-6578) after hours. You may also use NextMD if this is not an emergency
- Aman Singh, M.D.
To contact Dr. Singh, please call the office (314-997-0554) during regular business hours or the exchange (314-388-6578) after hours. You may also use NextMD if this is not an emergency.
- Carrie Meyer, MS, PA-C
To contact Carrie Meyer, MS, PA-C, please call the office (314-997-0554) during regular business hours or the exchange (314-388-6578) after hours. You may also use NextMD if this is not an emergency.
- Caroline Chang, MMS, PA-C
To contact Caroline Chang, MMS, PA-C, please call the office (314-997-0554) during regular business hours or the exchange (314-388-6578) after hours. You may also use NextMD if this is not an emergency.
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Telephone Calls
Routine telephone calls should be made between 9:00 AM and 4:45 PM Monday through Friday. Emergency telephone calls after office hours should be directed to the exchange (314) 388-6578. True medical emergencies that can not wait should prompt a 911 call. Return telephone calls by physicians will be made throughout the course of the day – please tell us how long you will be at your telephone number and how urgent the problem is. We perform endoscopic procedures most mornings and return calls in between cases or at the end of the work day for elective calls.
You may also use NextMD if this is not an emergency.