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Patient Education · United Gastroenterology Associates
Patient Education: GI Visits, Procedures and Results
This page explains how visits and procedures work at United Gastroenterology Associates, PLLC: how to schedule an endoscopy or colonoscopy, what to bring, what happens on procedure day, how sedation works and when results are ready. Procedures are performed by Muhammad Ali Khan, MD, FACP, FASGE, a board-certified gastroenterologist with offices in Katy and Cypress. Call (346) 340-4414 with questions.
Questions: (346) 340-4414
Meet Your Gastroenterologist: Muhammad Ali Khan, MD, FACP, FASGE
BOARD-CERTIFIED Gastroenterologist and Hepatologist
CREDENTIALS AT A GLANCE
Board-Certified
Gastroenterology, hepatology, and internal medicine
Academic Medicine
Former Associate Professor, UT MD Anderson Cancer Center
Published Research
More than 100 peer-reviewed articles in gastroenterology
FACP and FASGE
Fellow, American College of Physicians and American Society for Gastrointestinal Endoscopy
“My gastroenterology & hepatology practice is dedicated to working closely with you to develop a personalized treatment plan that meets your unique needs and preferences.”
Dr. Muhammad Ali Khan, MD, FACP, FASGE
Board-certified gastroenterologist and hepatologist, United Gastroenterology Associates
Procedures at United Gastroenterology Associates are performed by Dr. Khan, a gastroenterologist board-certified in gastroenterology, hepatology and internal medicine and a Fellow of the American Society for Gastrointestinal Endoscopy (FASGE).
Dr. Khan is a former Associate Professor at The University of Texas MD Anderson Cancer Center and has authored more than 100 peer-reviewed publications.
Procedures
- Colonoscopy
- Upper endoscopy (EGD)
- Flexible sigmoidoscopy
- ERCP
- Polyp removal and biopsies
What to Expect at United Gastroenterology Associates
Most patients start with a consultation. Dr. Khan reviews your symptoms, history and earlier tests, then decides whether you need an endoscopy, colonoscopy or another test. If a procedure is needed, the office schedules it for another day, and a nurse explains how to prepare.
On procedure day, you arrive 45 minutes early, receive sedation from a board-certified anesthesiologist, and usually spend about 2 to 2½ hours at the center. You go home with your findings, color photos from the exam and written instructions.
How to Schedule an Endoscopy or Colonoscopy
From your first call to your procedure date.
Call the office
Call (346) 340-4414 to make a consultation appointment with the gastroenterologist.
Referral, if needed
If your insurance requires a referral from your primary care physician, the office can help you obtain it.
Consultation
Dr. Khan evaluates your symptoms and history and decides whether an endoscopic exam is needed.
Scheduling
If a procedure is needed, the front office schedules it for another day.
Your Procedure Day at a Glance
A typical endoscopy or colonoscopy day at the endoscopy center.
| Step | What happens |
|---|---|
| Arrival | Arrive 45 minutes before your exam time to sign consent forms and review post-procedure instructions. |
| Preparation | A nurse reviews your medical history and places a small IV catheter. |
| Sedation | A board-certified anesthesiologist gives Monitored Anesthesia Care (MAC) sedation, so you are asleep. |
| The exam | Usually 15 to 45 minutes, depending on what is found, such as polyps that are removed during the exam. |
| Recovery | At least 30 minutes of monitoring as the sedation wears off. |
| Total time | Plan on about 2 to 2½ hours at the center. An adult must drive you home. |
When Are Colonoscopy and Upper Endoscopy Recommended?
Colonoscopy is recommended for colorectal cancer screening starting at age 45 for most adults, and to evaluate symptoms or risk factors such as a change in bowel habits, blood in the stool, abdominal pain, weight loss, anemia, constipation, diarrhea, a family history of colon cancer, a personal history of colon polyps or inflammatory bowel disease. See colorectal cancer screening guidelines.
Upper endoscopy (EGD) examines the esophagus, stomach and duodenum. It may be recommended for reflux that does not improve with treatment, trouble swallowing, upper abdominal pain, ongoing nausea or vomiting, signs of bleeding or anemia, or biopsies to check for H. pylori or celiac disease. Read what happens during an upper endoscopy.
Bring to every visit
- Insurance card and photo ID
- Emergency contact name and phone number
- List of current medicines
- List of allergies
- An adult driver if you are having a procedure
Copies of earlier test results are helpful too.
After Your Procedure
Most patients feel back to normal or a little sleepy afterward. Many go home, take a nap and return to regular activities the next day. Do not drive for the rest of the day.
Before you leave, your physician writes the findings and instructions on your post-procedure sheet, goes over them with you and gives you color photos from the exam. A copy is sent to your primary care physician the same day. If biopsies were taken, pathology results usually take about 3 to 5 days, and the office will call you or schedule a follow-up appointment.
Call the office or seek care after a procedure for:
Severe abdominal pain, fever, vomiting, or more than a small amount of bleeding. For a medical emergency, call 911 or go to the nearest emergency room.
Patient Education Topics
Guides written for patients of United Gastroenterology Associates.
Preparing for a Procedure
Colonoscopy prep instructions, how to prepare for a colonoscopy, ERCP prep and all procedure preparations.
Understanding Procedures
Endoscopy vs. colonoscopy, what a colonoscopy detects and screening vs. diagnostic colonoscopy. Start with what a digestive disease specialist does.
Screening and Prevention
Colorectal cancer screening, positive Cologuard test and preventive health counseling.
Insurance and Cost
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Patient Education FAQs
Answers to common questions about visits, procedures and results.
How do I schedule an endoscopy or colonoscopy?
Call the office at (346) 340-4414 to make a consultation appointment with the gastroenterologist. The visit determines whether you need a procedure. If your insurance requires a referral from your primary care physician, the office can help you obtain it. If a procedure is needed, the front office schedules it and a nurse explains how to prepare.
How long will I be at the endoscopy center?
Plan on about 2 to 2½ hours in total. You arrive 45 minutes before your exam time, the procedure itself usually takes 15 to 45 minutes, and you recover for at least 30 minutes afterward.
Will I be asleep during the procedure?
Yes. A board-certified anesthesiologist gives Monitored Anesthesia Care (MAC) sedation, so you are asleep during the exam.
What should I bring to my visit or procedure?
Bring your insurance card, your emergency contact's name and phone number, and a list of your current medicines and allergies. If you are having a procedure, an adult must bring you and drive you home.
How will I feel after the procedure?
Most patients feel back to normal or a little sleepy. Many go home, take a nap and return to regular activities the next day. You should not drive for the rest of the day.
When will I get my results?
Your physician reviews the findings with you after the procedure, gives you color photos from the exam and sends a copy to your primary care physician. If biopsies are taken, pathology results usually take about 3 to 5 days, and the office will call you or schedule a follow-up visit.
Why don't more people get screened for colon cancer?
Common reasons include feeling fine, worry about the bowel prep, and not knowing screening starts at 45. Early colorectal cancer and polyps often cause no symptoms, which is why screening matters. Ask the office about the screening options that fit you.
United Gastroenterology Associates Offices
Patients from Houston, Katy, Cypress, Fulshear, Richmond, Rosenberg and nearby communities are seen at both offices.
United Gastroenterology Associates – Katy
Katy Freeway (I-10) near the Grand Parkway
- Address: 23920 Katy Freeway, Suite 555, Katy, TX 77494
- Phone: (346) 340-4414
- Hours: Monday–Friday, 8:30 AM–5:00 PM (closed 12:00–1:30 PM for lunch; last appointment 4:30 PM)
United Gastroenterology Associates – Cypress
Northwest Freeway (US-290) in Cypress
- Address: 21216 Northwest Freeway, Suite 640, Cypress, TX 77429
- Phone: (346) 340-4414
- Hours: Monday–Friday, 8:30 AM–5:00 PM (closed 12:00–1:30 PM for lunch; last appointment 4:30 PM)
Have Questions Before Your Visit?
Call (346) 340-4414 or request an appointment. The team can explain scheduling, preparation and what to bring.
Sources
- National Institute of Diabetes and Digestive and Kidney Diseases. Colonoscopy. niddk.nih.gov
- National Institute of Diabetes and Digestive and Kidney Diseases. Upper GI Endoscopy. niddk.nih.gov
This page provides general information for patients of United Gastroenterology Associates and does not replace personal medical advice. Follow the instructions you receive from the office. For a medical emergency, call 911. Last updated October 5, 2026.