How to prep for a sigmoidoscopy & colonoscopy

by | Aug 4, 2021 | Endo Living

If you suffer from Endometriosis you will most likely have to do a sigmoidoscopy or a colonoscopy procedure at some point in your diagnosis journey. I have a few under my belt now, especially after being diagnosed with bowel endometriosis. From everything that I had to endure because of my illness, this is my least favorite procedure and it gets me extremely anxious every time that I am asked to get it done. But if you prepare correctly, you won’s have to repeat it as many times as I had. Here are some tips on how to prepare for a sigmoidoscopy or colonoscopy. Endometriosis is a very misunderstood illness and bowel endometriosis can be even more confusing, so it is important to learn about it so you can advocate for yourself once you are at the doctor. Bowel endometriosis is often misdiagnosed as irritable bowel syndrome (IBS), occurs when lesions grow on the peritoneum (the membrane lining the inside of the abdomen and covering the abdominal organs), the rectum, the intestines, and other deeper bowel levels. The risk of not having an accurate bowel endometriosis diagnosis means that the disease progresses and the quality of life significantly decreases. What started as small lesions on the bowel can eventually progress and become full-thickness lesions causing obstruction and may require major bowel surgery. An early endometriosis diagnosis can lead to successful excision surgery and better quality of life.

I wanted to start by explaining what is gastroenterology? The medical especially to the study, diagnosis, and treatment of disorders of the digestive system. These disorders may affect the esophagus, stomach, small intestine, large intestine (colon), rectum, liver, gallbladder, or pancreas.

Ok! now I want to mention the difference between them both.

What is Sigmoidoscopy ?

Sigmoidoscopy is a procedure done by a gastroenterologist doctor that allows them to look at the rectum and sigmoid colon (large intestine). In this procedure, a thin flexible tube with a light on the end is passed into your rectum. This procedure only examines the lower 20 inches of the colon. This test is done to help your doctor diagnose your condition and prescribe a treatment. It can evaluate and treat problems such as changes in bowel habits (diarrhea or constipation), rectal bleeding, rectal pain, rectal mass, screening for colorectal cancer, etc. Tissue samples can also be taken at this time. Like with any invasive procedure, complications may occur like bleeding after biopsy or perforation of the intestine wall (rare cases).

The best way to prepare for a sigmoidoscopy is to follow your doctor’s instructions to the last detail. In my case, I was asked to administer two rectal sodium phosphate enemas bought from the drug store, 1-2 hours prior to my scheduled appointment and 15 minutes apart. I followed the instructions on the package on how to put them on. Also, do not eat anything after midnight the night before the surgery or in the morning, only drink some allowed fluids. If you are traveling a long distance it is best to allow extra time to give yourself the enema when you arrive at the doctor rather than doing it at home.

The sigmoidoscopy usually takes 5-10 minutes, you will likely be positioned on your left side. The sigmoidoscope will be lubricated before being inserted into your rectum. Air will be put into your sigmoid colon to allow the doctor to see the area better, this may give your abdominal cramping and/or the urge to have a bowel movement.

After the procedure, you may see a small spot of fresh blood on the toilet tissue used to wipe yourself if you have tissue samples taken. If you note larger amounts of blood that persist or are excessive please go to the emergency. Some doctors may discuss the finding right away or they may choose to do so at a follow-up appointment. You may return to work and usual activities as soon after the procedure because NO sedation will be used.

My best advice here is to follow the prep instructions as the quality of the findings depends on it. I would also suggest asking for some sort of sedation if possible, most people feel some discomfort but not pain. Unfortunately, I was one of the few that experienced a lot of discomfort and pain. Being relaxed and breathing can make the exam a lot more pleasant as the muscles are more relaxed and less tense. I would suggest being very expressive and letting the doctor know if you are experiencing pain during the procedure so they can adjust accordingly. When I had my sigmoidoscopies done, it was because I was experiencing rectal bleeding an entire week before my period. I would recommend scheduling the exam at the time of your menstrual cycle where you are having gastrointestinal problems so you have more chances of the lesion showing up. I had the same exam at a different time during my menstrual cycle and the lesion was not visible. Being able to visualize lesions on your sigmoidoscopy can help with your endometriosis diagnosis so it is important to understand your menstrual cycle symptoms and to schedule this procedure accordingly.

*Please note that the lesions will only show up if you have deep endometriosis, meaning that the endometriosis lesions infiltrated deep in the walls of an organ in this case, the colon or rectum.

What is a colosnoscopy?

Colonoscopy is a procedure done by a gastroenterologist doctor that allows them to look at the rectum and entire colon. During the procedure, a long flexible tube (colonoscope) is inserted into the rectum and passed around the entire colon. On the end of the scope is a tiny camera and light source which allows the doctor to view inside of the colon. You will be given sedation during this procedure. The procedure itself is around 20-30 minutes to complete. This test is done to help your doctor diagnose your condition and prescribe a treatment. It can evaluate and treat problems such as changes in bowel habits (diarrhea or constipation), rectal bleeding, rectal pain, rectal mass, screening for colorectal cancer, etc. Tissue samples can also be taken at this time. Like with any invasive procedure, complications may occur like bleeding after biopsy or perforation of the intestine wall (rare cases).

“The most important thing you can do to have a successful colonoscopy is to properly prepare your bowel”

The large bowel must be cleaned out to allow for thorough examination of the bowel wall and therefore, detection of any abnormalities. An excellent bowel preparation improves the quality and the safety of the procedure. a poor bowel preparation increases the risk of missing significant abnormalities and increases complications not to mention the need to repeat the test.

Ok! for the colonoscopy the worse part is the preparation and this is something that you would have to do yourself and at home. It all starts 4 days prior to the colonoscopy where you have to eat a low fiber diet. They suggest avoiding eating nuts, popcorn, kiwis, or foods with seeds. Avoid eating raw fruits, vegetables, whole wheat or high fiber bread, and any fiber supplement. Do not have any clear fluids that are red, green, blue, or any dark-colored beverages, including Jell-o.

The bowel is prepped using an oral PEG-based laxative and the fluids that you drink. PEG-based laxatives are sold under different names including Colyte, Peglyte, and Golytely. These are very powerful laxatives that will give you diarrhea meant to clean you out. Individual responses may vary, you may begin having bowel movements within 1 hour, or it makes take up to 4 hours. Prepare the PEG laxatives according to the instructions on the bottle the day before the procedure. In the morning the day before the procedure, prepare the PEG laxative according to the instructions on the bottle, do it in the morning and refrigerate. This is a super tip: Make sure the prepared laxative is cold by the time that you drink it because it tastes “better” cold- in my opinion.

The day before the procedure you can only drink clear fluids after a low fiber breakfast (white toast, tea, or coffee). You are not allowed to consume any solid food or dairy products after that light breakfast until after the procedure. In the afternoon the doctor will give you a specific time to start taking the laxative, the time is dependant on the time of your procedure the next day. 2 liters of laxative have to be consumed within 2 hours, it is about 8oz glass every 10 minutes. This is the most important and hard step! a tip here is to try to drink it with a straw as you will drink it faster. Tip: The bowel preparation will taste better if kept cold. It is important to continue drinking clear fluids throughout the remainder of the day to prevent dehydration. Tip: If you experience nausea as I did, you may try drinking ginger-ale, or take 30 min break from drinking the prep, or just use Gravol (take Gravol 30 min prior to drinking the prep to give it the best chance to work).

On the day of the colonoscopy, 6 hours before your procedure you will drink the remaining 2 liters of PEG laxative within 2 hours. You can drink clear fluids and take the required medication until 2 hours before your procedure. It is important NOT to eat any solid food the day of the procedure. Tips: Remember not to drink anything red in color, it is best if you drink sports drinks such as Gatorade, or PowerAde, or clear soup broths to replace electrolytes and hydrate rather than just drinking water. If you are on your period there is no problem because it is safe to have a colonoscopy while you are on your period and it will not interfere with the exam.

Final thoughts, for the colonoscopy I would suggest staying home the day before the procedure to prep well as you would go to the bathroom a lot with diarrhea. Please remember to keep a positive attitude and remember that everything will pass, sometimes when we feel sick and we are going through all of this the “why me?’ question invades our mind and it makes it harder emotionally. Switching our mindset to a more positive one will bring a better outcome, instead of thinking why me? I was grateful to have the opportunity to have this procedure done, to be one step closer to finding out the reason why I was in so much pain. I saw it as a lucky opportunity that many didn’t have and it gave me strength and a new perspective on everything that was happening to me at that time. After the surgery, you would need someone to drive you home because of the sedation that they use for the colonoscopy but it will wear off soon after the procedure and I was able to continue with my daily activities without any problems. Thankfully for the colonoscopy, you are sedated so it doesn’t hurt and you don’t feel anything. The tedious part about having a colonoscopy is feeling sick when having to drink the laxative and the emotional turmoil it brings out in us but the procedure itself is a breeze.

I really do hope that this post serves you well and that you can go into this healing journey confident with a new set of tools on what to expect. Feel free to write to me or comment if you have any questions or you need some support if you are going through this right now.

*Disclaimer: I am not a doctor and you should consult your doctor and follow their instructions. This post is my experience, what worked for me, and the tips that I believe will help you.

With love,

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About Me

Welcome! I’m Ana. I started Endo Culture because I want to give women that are suffering from endo a place where they can find tools, information, and tips on how to thrive with this chronic illness.

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Is a mindful brand that I created as a result of my endometriosis health journey. It is for endometriosis and chronic pelvic pain sufferers. With my experience managing chronic pain for over two decades, I learned of holistic alternatives that help greatly. My purpose is to help others relieve some of the pain experienced during their menstrual cycle in a more natural and comfortable way.

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