What is Colonoscopy? How is Colonoscopy Performed? Preparation Process (Step-by-Step Guide)

Colonoscopy is an important endoscopic procedure that can be performed for both diagnostic and therapeutic purposes, and is most often referred to as a “colonoscopy”. it is understandable why questions such as “What is a colonoscopy?”, “How is a colonoscopy performed?” and especially “colonoscopy preparation” are so frequently asked: More than the procedure itself, the preparation process can be intimidating; one also wonders about sedation/anesthesia, whether there will be pain during the procedure and the post-procedure process.

In this article, we will discuss what a colonoscopy is, in which cases it is requested, step-by-step answer to the question of how to perform a colonoscopy, and the most critical part, colonoscopy preparation (3 days before - 1 day before - the morning of the procedure) with a clear timeline. We will also explain colonoscopy diet, pos-free diet, transparent liquid diet, intestinal cleansing (laxative) and nutrition/normal symptoms/warning signs after colonoscopy in a practical language.

Note: This content is for general information purposes. Always follow your doctor’s instructions for your medications (especially blood thinners, diabetes medications/insulin, iron preparations) and any additional diseases.

What is a Colonoscopy (Large Intestine Examination)?

Colonoscopy is the visualization of the large intestine (colon) and often the last part of the small intestine by entering through the rectum with a thin, flexible device (colonoscope) with a camera and light at the end. It is also commonly known as a “colonoscopy”. Colonoscopy is not just for “looking”; some procedures can also be performed in the same session:

• Biopsy: Taking a small tissue sample from the suspicious area (usually no pain is felt).
• Polyp removal (polypectomy): If colon polyps are detected, appropriate ones can be removed during the procedure.
• If there is a bleeding focus, in some cases interventions to stop bleeding may be performed.

The success of a colonoscopy largely depends on good bowel cleansing. In other words, the better the “colonoscopy preparation” is, the easier it is for the doctor to see the intestinal wall; even small polyps cannot be missed. Therefore, planning the preparation process correctly directly affects the quality and reliability of the process.

Related content: What you need to know about colon cancer screening and What is colon polyps?

Why is a colonoscopy performed? Which Complaints Are Requested?

Colonoscopy can be ordered both to investigate complaints and for screening purposes. Most common causes:

Colonoscopy for complaint (diagnostic) purposes

Your doctor may recommend a colonoscopy in the following cases:

• Bowel bleeding or blood in the stool
• Anemia (iron deficiency anemia) especially if the cause is unexplained
• Change in bowel habits: Prolonged diarrhea, constipation, thin stools, marked change in bowel movements
• Abdominal pain, bloating, unexplained weight loss
• Suspicion or follow-up of inflammatory bowel disease (ulcerative colitis/Crohn’s)
• Suspicious finding in the colon on imaging tests (CT/MR)

Screening colonoscopy

Colorectal cancer screening is planned according to age and risk status. If there is a family history of colon cancer, previous polyps or certain genetic syndromes, screening may be considered earlier and more frequently.

A frequently asked question at this point: “Fecal occult blood test or colonoscopy?” In some people, methods such as FIT / fecal occult blood test can be used for screening; however, in case of positivity, a clear evaluation with colonoscopy is usually required. For details: What is a fecal occult blood test (FIT)?

How is Colonoscopy Performed (Step-by-Step Procedure)

the answer to the question “How is a colonoscopy performed?” reduces anxiety for most people. The general flow is as follows:

1) Admission to hospital/clinic and preliminary preparation

• Registration is done and a brief assessment is made (complaints, diseases, allergies, medications used).
• An IV can be started and serum/medications are given if necessary.
• The sedation/anesthesia plan is clarified.

2) Sedation/anesthesia (Colonoscopy anesthesia/sedation)

Colonoscopy is often performed with sedation. This ensures that the person is relaxed and often does not remember the procedure. The level of sedation may vary depending on the center and the person:

• Mild sedation: You may be drowsy, you may respond to commands.
• Deeper sedation: You usually do not remember the procedure.

the answer to the question “Does colonoscopy hurt?” takes shape here: With sedation, most people do not feel significant pain; sometimes there may be a feeling of pressure/bloating due to gassing.

3) Implementation of the process

• The colonoscope is inserted through the anus and the large intestine segments are evaluated one by one.
• If necessary, a biopsy or polyp removal is performed.
• The duration of the procedure varies according to the person. for the question “How many minutes does a colonoscopy take?” average: 15-45 minutes (may take longer depending on polyp/biopsy, bowel structure and cleaning).

4) Awakening and brief observation

If sedation is given, you will be followed in the recovery area for a while. Discharge is usually on the same day.

Important: If you are sedated, you should not drive after the procedure, you should not make important decisions and if possible, you should have a companion with you.

Colonoscopy Preparation (The Most Critical Part): 3 Days Left - 1 Day Left - Trade Morning

“Colonoscopy preparation” has two main goals:

1. Reducing pulp (pulp-free diet)
2. **Ensuring complete emptying of the colon with bowel cleansing

The following plan is the most common general approach; your doctor may prescribe a different protocol.

3 days to go Pulp-free diet before colonoscopy

Objective: Reducing fibrous foods that can leave “residue” in the intestine.

What is usually recommended (examples):

• White bread, rice pilaf, pasta
• Non-fat/low-fat yogurt (unless your doctor tells you differently)
• Eggs, cheese (without excessive fat)
• Boiled/grilled chicken, fish
• Strained soups (grain-free)

What is usually avoided:

• Wholegrain products, oats, muesli
• Legumes
• Raw vegetables/salad, corn
• Stone fruits, dried fruits
• Grainy foods such as nuts, sesame seeds and black cumin

Micro questions (long-tail):

• “Can I eat bananas before colonoscopy?” In some plans, bananas may be considered limited, but not all centers agree. It is best to follow your doctor’s diet list.
• “Can I eat yogurt before colonoscopy?” It can be limited in most pulp free diet plans; nevertheless, it is usually switched to clear liquid 1 day before the procedure.

1 day to go: Transparent liquid diet + start of bowel cleansing

Most protocols today include solid food withdrawal and transparent liquid diet.

Examples of a clear liquid diet:

• Su
• Open tea (without milk)
• Pulp-free, clear fruit juices such as apple juice (avoid red/purple colored drinks)
• Broth/chicken broth (grain-free)
• Drinks containing electrolytes recommended by the doctor

“Can I drink coffee before colonoscopy? “ It may be limited if milk/cream is not added and the doctor allows it; however, some protocols may not recommend it at all.
“Can I have soup before a colonoscopy? “ Some soups may be considered appropriate, provided they are grain-free, filtered and clear.

Bowel cleansing (laxative) Follow the medication schedule given by your doctor exactly. In general

• frequent and watery stools are expected after taking the medicine.
• Side effects: Nausea, abdominal cramps, feeling cold, weakness.

**What to do if vomiting occurs Taking short breaks and continuing with small sips works for some people, but if vomiting is severe or you cannot hold the medicine down, contact your healthcare team.

The morning of the procedure: Fasting period and final checks

• “How many hours should I fast before a colonoscopy?” It depends on the sedation/anesthesia plan; in most places there is no solid food after a certain time and fluid intake is stopped before a certain time. Follow your doctor’s instructions.
• “Can I drink water the morning of the colonoscopy procedure?” Small sips are usually allowed up to a certain time or you may be asked to stop drinking completely; this decision depends on the sedation protocol.
• For regular medications (blood pressure medication, etc.), your doctor may say “take it with less water”; do not decide on your own.

Critical warnings about medicines used

• Blood thinners (aspirin, clopidogrel, warfarin, etc.): there is no single answer to the question “Should blood thinners be stopped before colonoscopy?”. The possibility of polyps, your cardiovascular risk and the type of medication are decisive. It is always planned with your doctor.
• Diabetes medicines/insulin: Dose may need to be adjusted as you will be hungry.
• Iron medications: Some protocols require discontinuation a few days in advance (may affect the image).

The Post-Colonoscopy Process: Nutrition, Normal Complaints and Alarm Signs

the most common conditions in the “post-colonoscopy” period are usually temporary:

Conditions that can be considered normal after the procedure

• Gas and bloating: caused by air/CO₂ given during the procedure.
• Mild cramping abdominal pain
• Sedation-induced drowsiness, sleepiness

for the question “When can I eat after colonoscopy?” After the sedation wears off, you can usually start with light food when your doctor gives permission. on the first day of “post-colonoscopy nutrition”, easily digestible options such as soup, yogurt, rice porridge can be preferred (depending on your personal situation).

Alarm signs to watch out for (may require emergency admission)

Contact your healthcare provider without delay in the following cases:

• Severe and increasing abdominal pain
• Intense rectal bleeding or bleeding with clots
• High fever, chills
• Fainting, severe weakness
• Shortness of breath (rare but important after sedation)

If a biopsy was taken or the polyp was removed, your doctor may make additional recommendations after the procedure. The time for the pathology result varies depending on the center; most of the time it can be in the range of a few days to a few weeks.

Related content: What is endoscopy, how is it done? and Nutrition recommendations after colonoscopy

Frequently Asked Questions (About Colonoscopy Preparation and Procedure)

Does a colonoscopy hurt?

Most people do not feel significant pain during a sedated colonoscopy. Some people may have pressure/bloating due to gas.

How many minutes does a colonoscopy take?

It usually takes between 15-45 minutes. Polyp removal/biopsy and adequacy of bowel cleansing affect the duration.

Can I eat yogurt before colonoscopy?

it may be part of some plans during the “pulp-free diet before colonoscopy” period, but the day before the procedure, you usually switch to a transparent liquid diet. Follow your doctor’s list.

Should I have soup before colonoscopy?

Some soups may be suitable as long as they are grain-free and clear; creamy, grainy or fibrous soups are generally not recommended.

Can I drink coffee before colonoscopy?

It can be limited without added milk/cream and if your doctor allows it; some protocols may not recommend it at all.

Can I get information about colonoscopy prices?

“Colonoscopy prices” vary from institution to institution; factors such as type of sedation, biopsy/polyp removal, pathology and insurance/SGK coverage are determinative. For the net price, an examination and procedure plan is required. (It is usually more accurate to prepare a detailed guide page for this topic separately)

Colonoscopy is a very valuable diagnostic/treatment method with the right indication, in the appropriate center and especially when colonoscopy preparation is performed correctly. Think of the preparation process not as a “burden” but as the most important step that determines the quality of the procedure. Following the diet and bowel cleansing plan given by your doctor exactly will help the procedure to be shorter and more comfortable and to achieve the right result.