FAQ as You Prepare for Your Colonoscopy or Upper Endoscopy

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Frequently Asked Questions as You Prepare for Your Colonoscopy or Upper Endoscopy
Thank you for choosing to have your procedure with Mass General Gastroenterology Associates. Patients often have questions as they prepare for their colonoscopy or upper endoscopy. Below are answers to some frequently asked questions.
Information on preparing for your procedure can also be found in the bowel preparation packet that you received in the mail. If you still have questions after reviewing your bowel preparation packet and the information below, please call the GI office at 617-726-7663.
Medicines
Do I need to stop taking my blood thinner?
If you take blood thinners, we recommend you take them unless your gastroenterology doctor told you to stop taking them. We also encourage you to communicate with your prescribing provider (heart doctor or primary care provider). Blood thinners may include Coumadin, Plavix, Pradaxa, Eliquis and Lovenox.
If I had a knee replacement, should I take antibiotics ?
If you previously had a knee replacement, antibiotics are generally not needed to prevent joint infections. However, if your orthopedic doctor or primary care doctor recommends antibiotics, please contact their office for a prescription and instructions.
If I had a heart valve replacement, should I take antibiotics?
If you previously had a heart valve replacement, antibiotics are generally not needed to prevent valve infections. However, if you have a high-risk heart condition, antibiotics may be recommended. Please check with your heart doctor to see if antibiotics are recommended for you.
Can I continue my vitamins, iron pills, or liquid antacids?
If you take vitamins, iron pills, or liquid antacids, stop taking them 5 days before your procedure. Liquid antacids include Mylanta and Gaviscon. If you are unsure, check with your prescribing provider.
Should I take my medicine for diabetes?
If you are taking Canagliflozin (Invokana), Canagliflozin and Metformin (Invokamet), Dapagliflozin (Farxiga), Xigduo XR Dapagliflozin and Metformin extended-release, or Empagliflozin (Jardiance), please stop it at least three days before your colonoscopy. If you are taking ertugliflozin (Steglatro, Steglujan, or Segluromet), please stop it at least four days before your scheduled colonoscopy. Make sure to contact your primary care physician or diabetes doctor about the suggested changes above and get their guidance as well
If you take insulin, we usually recommend that you take ½ your normal dose on the day of the procedure.
Should I take other medicines prescribed for me?
Contact the provider who prescribed the medicine for you about any changes needed before your procedure. In general, we recommend that you take your usual medicine as prescribed when possible.
Bowel Prep Laxative
What should I do if a prescription for laxative wasn’t included in my bowel preparation packet?
Some bowel preparations require prescription laxative. If your bowel preparation instructions say that you will need to take prescription laxative, your prescription will be sent electronically to your pharmacy. Many pharmacies place these prescriptions on hold, so contact your pharmacy and ask to have it filled.
What should I do if my pharmacy hasn’t received the prescription for laxative yet?
Please call your pharmacy first. If your pharmacy does not have the prescription for laxative, please call your gastroenterology doctor’s office for a prescription. If your procedure is more than 1 week away, you may also send a Patient Gateway message to request a prescription at patientgateway.massgeneralbrigham.org
I was given PEG laxative. Is it the same as GoLYTELY?
Yes, PEG and GoLYTELY laxatives are the same. The generic name is PEG-3350 with Electrolytes (polyethylene glycol electrolyte solution). Brand names include GoLYTELY, NuLYTELY, Colyte, Trilyte, or GaviLyte.
What if a prior authorization is needed for my prep/laxative?Please check with your insurance upon scheduling to understand if your prep requires a prior authorization (insurance coverage). It is important to you notify the office as soon as possible to avoid scheduling issues.
I took magnesium citrate as a laxative the last time. Can I have that this time?
We no longer recommend magnesium citrate as a laxative for our patients. Magnesium citrate doesn’t work as well and can have more risks and side effects than other laxatives.
My friend had a laxative that was easier to drink. Can I have a different laxative?
We strongly recommend that you use the laxative prescribed for you. Other laxatives may not work as well, may not be covered by your insurance, and can be more expensive.
Do I need to drink half of the laxative the night before my procedure and half the morning of my procedure?
Yes, it is important to drink half of the laxative the night before your procedure and half the morning of your procedure. Make sure you follow the schedule in your bowel preparation packet carefully. Following this schedule will clean your bowels completely and allow your gastroenterology doctor to see inside your colon better.
If your bowels are not clean, your procedure may get postponed, cancelled, or need to be repeated. You may also be given a different bowel preparation to clean your bowels better.
Please follow our instructions and disregard the bottle which may tell you to take the laxative all at once.
Do I need to wake up in the middle of the night to finish drinking the laxative?
It is very important that you finish the laxative 4 hours before your scheduled arrival time as instructed in your bowel preparation packet. This may require you to wake up in the middle of the night to finish drinking the laxative. The correct timing of drinking the laxative is important in cleaning your bowels completely and allowing your gastroenterology doctor to see inside your colon better.
We understand early appointments and travel time may be difficult however please make every effort to follow the prep instructions, it is to your benefit to avoid having to re-schedule your procedure for poor prep.
You may drink a small amount of clear liquids up until 2 hours before your procedure.
If your bowels are not clean, your procedure may get postponed, cancelled, or need to be repeated.
Can I drink all the laxative the night before my procedure?
No. It is important to follow the schedule in your bowel preparation packet. Drinking the last half of the laxative closer to your procedure time will give better results and a cleaner colon for your procedure.
If your bowels are not clean, your procedure may get postponed, cancelled, or need to be repeated. You may also be given a different bowel preparation to clean your bowels better.
What should I do if I have a long travel time to MGH for my procedure?
If you have a long travel time to MGH for your procedure, we recommend that you drink the last half of the laxative earlier. For example, we generally recommend drinking the last half of the laxative 4-5 hours before your scheduled arrival time. However, if it will take you 2 hours to get to MGH, you may want to drink the last half of the laxative 6-7 hours before your scheduled arrival time instead. This will allow the laxative to work before you leave for your procedure.
What are some tips for drinking the laxative if I feel sick to my stomach?
It is common to feel nauseous or sick to your stomach during your bowel preparation. Here are some tips you can try to help you drink the laxative:
Rest for 30 minutes then continue to drink the laxative every 20-30 minutes as tolerated.
Use a straw to drink the laxative.
Chill the laxative in the fridge and drink it cold.
Add some fruit juice, Crystal Light, or ice to the laxative to help make it taste better. Don’t use any red, purple or orange colored fruit juice or Crystal Light.
Chew gum or suck on lemon or hard candy in between drinks to help with the taste.
These tips can also be found in your bowel preparation packet.
What if the amount of laxative will be too much for me to drink?
If you think the amount of laxative will be too much for you to drink, talk with your gastroenterologist about your options.
What should I do if I already drank the first half of the laxative, but haven’t had a bowel movement yet?
If you haven’t had a bowel movement after the first half of the laxative, continue to drink the laxative until you have a bowel movement then stop. In the morning, finish drinking the rest of the laxative as instructed in your bowel preparation packet.
Be sure to drink plenty of clear liquids to keep yourself hydrated.
What should I do if I have severe constipation or gastroesophageal reflux disease?
If you have a history of severe constipation, GERD (gastroesophageal reflux disease), or any other problems with digestion, contact your gastroenterology doctor at least 2 weeks before your procedure to discuss the right laxative and diet plan for you.
What should I do if I don’t think the laxative prescribed for me will clean out my bowels completely?
If you don’t think the laxative prescribed for you will clean out your bowels completely, contact your gastroenterology doctor at least 2 weeks before your procedure to discuss the right laxative and diet plan for you.
How can I tell if my bowels are clean before my procedure?
After finishing your laxative, your stool should be watery. The color of your stool should also be clear or yellow.
What do you recommend if I did not tolerate the prep for my last colonoscopy?
Please discuss prep options with your endoscopist and or primary care provider when the procedure is booked. It is important to have the best prep possible to ensure a thorough examination of your colon.
If I have constipation, what can I do improve this?
If you move your bowels 2 times a week or less or if you use a laxative more than 2 times a month, at bedtime, take 4 tablespoons of milk of magnesia.
Anti-Gas Pills
What are anti-gas pills?
Anti-gas pills are chewable simethicone tablets. They are available over the counter at your pharmacy. Some brand names include Gas-X, Maalox Anti-Gas, Mylicon, and Mylanta Gas. Any brand is fine. Please take two tablets of the regular strength simethicone. Ask your pharmacist if you would like help finding them. Please avoid the cherry flavor (red color).
Diet and Nutrition
I ate breakfast the morning of my procedure. Can I still have my procedure?
If you ate breakfast the morning of your procedure, your procedure must be rescheduled for a later date. To reschedule your procedure, please call [GI office/617-726-2426 option #3] as soon as possible.
It is important to follow the instructions in your bowel preparation packet carefully to prevent your procedure from getting rescheduled.
Arrival and Procedure Times
It is important to arrive at the time listed in your bowel preparation packet to allow us to get you ready for your procedure. This includes filling out paperwork, changing into a hospital gown, taking your vital signs, placing an IV (intravenous) catheter in your arm for medicine, and answering any questions you have about the procedure. Please arrive on time to prevent delays in starting your procedure.
How long will my procedure last?
Plan on spending about 3 hours total in the Endoscopy Unit. This includes time needed to prepare for the procedure, perform the procedure, and recover after the procedure.
Average length of each procedure:
Colonoscopy – 20-30 minutes
Flexible Sigmoidoscopy - 10 minutes
Upper Endoscopy - 10 minutes
The length of your procedure will depend on the type of procedure you will have and the care you will need during the procedure.
Escort
Why do I need an escort?
You will receive medicine to help you feel relaxed and comfortable during your procedure. It will take some time for the medicine to completely wear off after. For this reason, you will need an escort, an adult aged 18 or over, to come up to the endoscopy unit in person to pick you up. Ride services such as Uber, Lyft, etc will not suffice as an escort.
When you arrive for your procedure, you must provide the name and phone number of your escort. Before your procedure begins, we will confirm with you, the patient, that your escort will be able to pick you at the Endoscopy Unit and bring you home.
If we cannot confirm that you have an escort, your procedure will be rescheduled for a later date. We follow this policy strictly for the safety of our patients.
What time should my escort pick me up?
Your escort should be able to pick you up 30 minutes after we call them.
Procedure Questions
What is conscious (procedural) sedation? Will I be going to sleep?
It is combination of sedatives and narcotics. Our goal is not for you to go to sleep but for you to feel comfortable during the exam. You will feel the effects of the medications for a couple hours after the procedure. Therefore, you cannot drive the day of your examination.
What are the common complications that arise from colonoscopy or endoscopy?
The common complication from these procedures is related to conscious sedation. Many patients feel sleepy and tired after the procedures. After colonoscopy, bloating and cramps is common. The more serious complications include bleeding or perforation. Bleeding may occur after a polyp is removed. With significant bleeding, you will see fresh, red blood in your stool. A perforation of your bowel will cause severe abdominal pain and fever. For these serious complications, it is important for you to be evaluated quickly in the MGH emergency department or a one closer to you.
Post-Procedure Questions
What if I haven’t received my results from my procedure after 14 days?
Some mild gas pain may be expected following your colonoscopy. Walking can be helpful. If pain is persistent and accompanied by fever, chills, blood in stools, hard abdomen, abdominal swelling or inability to pass gas, you should seek urgent medical attention.
What is a biopsy and how to I get the report?
A biopsy is a sample of tissue taken during a procedure. Biopsies are often taken of ulcers, tumors, polyps, and abnormal tissue in order to examine the samples with a microscope. The reports are usually available in 10-14 days. After your procedure, you should receive a written letter with the biopsy results.
Will I see my physician after the procedure?
Since you will be receiving sedatives for your procedures, you may not remember much of the test or the discussions afterwards. You will have the opportunity to see your physician prior to the procedure and your discharge paperwork will inform you if polyps were removed or biopsies taken. The results of the procedure will be given to you in written form. This will help you remember what was found during the procedure. All reports are sent to the referring physician(s) after the procedure.
What if I am breast feeding?
If you receive anesthesia, please discuss with your pediatrician for recommendations for breast feeding after sedation/anesthesia.
Other GI Endoscopy Procedure Questions
What is an ERCP?
ERCP (endoscopic retrograde cholangiopancreatography) is a term for a procedure in which the bile and pancreatic ducts are examined with an endoscope. X-ray dye is injected into the ducts and x-ray pictures are taken. If there is a blockage, a stent will be placed to unblock the duct.
What is an MRCP?
MRCP (Magnetic Cholangiopancreatography) is a term for a uses a powerful magnetic field, radio waves and a computer to evaluate the liver, gallbladder, bile ducts, pancreas and pancreatic duct for disease. It is noninvasive and does not use radiation. A dye is used to better examine the given area.
What is an EUS?
EUS, or endoscopic ultrasound, is an endoscopic exam using an endoscope with an ultrasound probe on the tip of the scope. This type of exam is often performed to evaluate patients with abnormalities in the pancreas and tumors in the esophagus and stomach.
Endoscopic Procedures During COVID-19
Peter Carolan, MD, clinical chief of the Massachusetts General Hospital Division of Gastroenterology, and Norman Nishioka, MD, director of Endoscopy, discuss the safety measures that have been implemented at Mass General and explain the importance of getting the care you need without delay.
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