Endoscopy & Colonoscopy: Why They’re Done & What to Expect

04/17/2026

Minimally invasive, non‑surgical procedures like endoscopy and colonoscopy can be recommended by your doctor when certain symptoms or risk factors suggest disease in your body.

If you’ve been advised to undergo one of these procedures, read this detailed guide on endoscopy and colonoscopy. Understanding what they involve can help lower anxiety and prepare you better.

Read Also: When is arthroscopy the Right Choice for Joint Problems?

What is Endoscopy?

An endoscopy is a non-surgical procedure done to inspect structures inside your body up close. During an endoscopy, an expert places a long, thin tube (endoscope) inside your body until it reaches the organ they need to evaluate.

'Endoscopy' originates from 2 Greek word parts:

• Endo- means “inside” or “within.”
• -scopy: means “to look at, view, or examine."

Read Also: Getting Ready for Arthroscopy

Types of Endoscopy

The name of the endoscopy procedure usually reflects the organ your provider is checking. For example, a “colonoscopy” is an endoscopy that examines your colon.

The type of scope usually reflects the organ, too. So the endoscope used for a colonoscopy is called a colonoscope.

Procedure Name	Type of scope (examples)	Where the scope goes	Main area examined
Anoscopy	Anoscope	Through the anus	Anus and rectum
Arthroscopy	Arthroscope	Through a small incision near a joint	Inside of the joint (e.g., knee, shoulder)
Bronchoscopy	Bronchoscope	Through mouth or nostril	Trachea (windpipe) and lungs
Colonoscopy	Colonoscope	Through the anus	Entire large intestine (colon)
Cystoscopy	Cystoscope	Through the urethra	Urethra and bladder
Enteroscopy	Enteroscope	Mouth for upper, anus for lower	Small intestine
Esophagogastroduodenoscopy (EGD) / Upper endoscopy	Gastroscope	Through the mouth	Esophagus, stomach, first part of small intestine (duodenum)
Hysteroscopy	Hysteroscope	Through the vagina and cervix	Inside of the uterus
Laparoscopy	Laparoscope	Through small incision(s) in abdomen	Abdominal and pelvic organs (e.g., intestines, uterus, ovaries)
Laryngoscopy	Laryngoscope	Through mouth or nostril	Voice box (larynx)
Mediastinoscopy	Mediastinoscope	Through incision above breastbone	Mediastinum (space between lungs: heart, esophagus, windpipe area)
Neuroendoscopy	Neuroendoscope	Through small opening in skull	Brain and ventricular system
Proctoscopy (rigid sigmoidoscopy)	Proctoscope	Through the anus	Anus and rectum
Sigmoidoscopy (flexible sigmoidoscopy)	Sigmoidoscope	Through the anus	Rectum and sigmoid colon (lower part of colon)
Thoracoscopy (pleuroscopy)	Thoracoscope	Through small incision(s) in chest	Lungs and pleural space; nearby structures like diaphragm, esophagus, chest wall
Ureteroscopy	Ureteroscope	Through urethra and bladder	Ureters (tubes from kidneys to bladder)

Why it is Done | Reasons For Endoscopy

An endoscopy can detect diseases that affect your:

• Digestive system
• Head and neck
• Joints
• Nervous system
• Respiratory system
• Urinary system
• Reproductive system

What to Expect During Endoscopy

During endoscopy, you will receive general or local anaesthesia. Once you’re completely asleep, the provider gently inserts the scope until it reaches the area they want to examine. An endoscopy generally takes 30 minutes to two hours, based on the procedure type.

Some endoscopes can be used with instruments that allow the healthcare professional to:

• Seal wounds.
• Perform surgeries and place stents.
• Inject medicine.
• Stop internal bleeding.
• Remove damaged tissue or tumours.
• Fix blockages or widen organs that are too narrow.

Your doctor can recommend endoscopy if you are experiencing the following symptoms:

• Persistent heartburn or acid reflux
• Difficulty swallowing (dysphagia)
• Unexplained nausea or vomiting
• Upper abdominal pain
• Gastrointestinal bleeding
• Suspected ulcers or inflammation

What is Colonoscopy?

Colonoscopy is a type of endoscopy, which is done for an examination of the inside of your large intestine, which includes your colon, rectum and anus.

The term 'colonoscopy' originates from the Greek words:

• kólon (colon/large intestine)-: from "colon", meaning the large intestine.
• -scopy: from Greek "skopein", meaning “to look at, view, or examine".

Why Colonoscopy is Done

A colonoscopy may be preventive, diagnostic or therapeutic — and often, it’s all of these.

Colonoscopy might help diagnose the following diseases or conditions:

• Chronic colitis, such as ulcerative colitis or Crohn’s disease.
• Intestinal ischaemia and ischaemic colitis.
• Diverticulosis and diverticulitis.
• Ulcers and perforations.
• Large bowel obstructions.
• Colon cancer screening.
• Colorectal polyps and colorectal cancer.

What to Expect During Colonoscopy

During a colonoscopy, you will receive general or local anaesthesia. Once you’re completely asleep, the provider gently inserts a flexible tube via the rectum to view your colon to examine it. The procedure generally takes 30 minutes to two hours.

During your colonoscopy, the healthcare professional can:

• Remove polyps.
• Seal wounds and inject medications.
• Remove blockages.
• Place stents.
• Treat tissues with laser therapy.

Your doctor may recommend a colonoscopy if you are experiencing the following symptoms:

• Unexplained rectal bleeding or discharge.
• Unexplained changes in the bowel habits, such as diarrhoea, constipation or incontinence.
• Unexplained persistent abdominal pain and weight loss
• Unexplained lack of weight gain in children.

Conclusion

Endoscopy and colonoscopy are both modern diagnostic tools that provide valuable insights into your digestive health. Whether you’re experiencing unexplained symptoms or undergoing routine screening, these procedures can help detect issues early. This helps guide effective treatment, ensuring better long-term health outcomes.

FAQs

Q1: Endoscopy vs. colonoscopy. What is the difference?
A: 'Endoscopy' is a broad term for the procedures that use a flexible camera tube to look inside the body. Colonoscopy is one specific type of endoscopy used to examine the large intestine (colon) and rectum.

Q2: What are the reasons for endoscopy?
A: It investigates, diagnoses, and treats conditions of the digestive tract. Endoscopy finds out the underlying cause behind unexplained symptoms such as persistent pain, difficulty swallowing, or vomiting.

Q3: What are colonoscopy risks?
A: It is a safe procedure under professional guidance. However, can cause rare complications like uncontrolled bleeding from tissue removal, perforation, etc.

Q4: Is endoscopy for stomach pain?
A: Yes, endoscopy is often recommended to find the underlying cause of stomach pain, however it is not needed for every case.