Endoscopy is a common medical procedure used by many specialties — but for many, they will encounter their first endoscopy with a gastroenterologist. We spoke with Dr. Gulchin A. Ergun, a gastroenterologist at Houston Methodist, to understand all things endoscopy, and what you can expect should or when you need one.

What is an endoscopy?

An endoscopy is a tool where a camera is attached to a tube-styled instrument called a scope that allows doctors to look inside the body. Doctors can take pictures and videos of organs and other structures in the body, as well as diagnose and treat certain conditions affecting those parts of the body.

"In the GI world, endoscopy looks at the entire GI tract, starting from the esophagus through the stomach and small intestine to the colon," Dr. Ergun says. "Doctors can use other endoscopes in other areas of the body. Surgeons use laparoscopes. They're the same thing, but they're inserted in the belly or other organs when they do laparoscopic surgery. Gynecologists use it to look inside the uterus."

What are the different types of endoscopy?

There are many types of endoscopes used by doctors. "Oscopy" means viewing or examining through an instrument — and the prefix added before "oscopy" can tell you the organ or area of the body being examined, Dr. Ergun says. Types of endoscopy can include:

• Bronchoscopy: A bronchoscope is used to view the lungs
• Colonoscopy: A colonoscope is used to view the colon and rectum
• Cystoscopy: A cystoscope is used to view the urethra and bladder
• Laparoscopy: A laparoscope is used to view the abdominal area and pelvis
• Laryngoscopy: A laryngoscope views the larynx, or voice box, vocal cords and structures in the back of the throat.

Which endoscopy types are commonly used by gastroenterologists?

Dr. Ergun says that upper endoscopy and colonoscopy are both completed by gastroenterologists. When and why you would receive either comes down to a person's symptoms, current health and age.

Why might your doctor recommend an endoscopy?

An endoscopy can be used for screening, diagnosing and treating health issues.

"So, if you're healthy, but you hit a certain age you need to have your colon looked at to make sure you don't have colon cancer or polyps that would need to be removed because they can turn to cancer," says Dr. Ergun. "Those are called screening colonoscopies."

Screening endoscopy will largely come down to age and personal risk factors for a condition. For colonoscopy, the U.S. Preventive Services Task Force (USPSTF) currently recommends adults at average risk for colon cancer should receive a colonoscopy starting at age 45. Those with an increased risk of the condition, due to family history, Crohn's disease or ulcerative colitis, or certain genetic syndromes, may need to begin screening at a younger age. Work with your primary care provider to know when you should get your first colonoscopy.

A doctor will recommend an endoscopy if a person is experiencing active symptoms.

"Diagnostic or therapeutic endoscopy looks to see why someone is having symptoms and guide treatment," Dr. Ergun says. "For example, someone who has persistent heartburn, nausea and vomiting, or trouble swallowing would need an upper endoscopy. If someone sees blood in their stool, or has chronic unexplained diarrhea or abdominal pain, that should prompt someone to consider recommending an endoscopy done by board certified gastroenterologist."

What conditions can be detected by an endoscopy?

Gastrointestinal conditions that can be found by upper endoscopy include:

• Celiac disease
• Esophageal rings and webs
• Esophagitis
• Malabsorption
• Ulcer disease
• Inflammation of the stomach
• Tumors

Colonoscopy is used to identify colon polyps that can lead to colon cancer.

Can endoscopy be used as a treatment?

In addition to being a diagnostic tool, endoscopy is used to treat certain conditions.

"We can do all kinds of therapeutic treatments," Dr. Ergun says. "For example, someone comes in vomiting blood. We do an urgent endoscopy, and we see an ulcer, but we also see the blood vessel where it's bleeding. Through the scope, we have options to insert devices that can stop bleeding. We can clip it, cauterize it, even spray it with things that can stop bleeding."

During an endoscopy, Dr. Ergun says that tissue can be removed, just as polyps can be removed during a colonoscopy. This is called a polypectomy.

"We put a little lasso around the polyp itself, and you can remove them," Dr. Ergun says. "If the opening from the bile ducts to the small intestine is too tight, they can cut it. They can even take gallstones out of bile ducts using these instruments. So there are a lot of treatments that can be done using an endoscope."

How does someone prepare for an endoscopy?

Dr. Ergun says that to prep for upper endoscopy, fasting is required. People will likely be asked not to eat anything after midnight the night before the procedure to ensure the stomach is empty.

"You can't put tubes in someone's stomach and esophagus if they have food in there," Dr. Ergun says. "There is a risk that people can aspirate when you sedate them. You're putting the scope down their throat — they're asleep, so they don't gag. You want to minimize anything that could be a risk."

For colonoscopy, there's a laxative preparation to make sure the colon is completely clean.

"Think of it this way," Dr. Ergun says. "If you went to a dermatologist, and you wanted to look at the hand to see if something's wrong with it, but someone put paint over, and you couldn't look at the skin. That's what an unprepared colonoscopy is like — except with feces. It's got to be clean. Those are the reasons that we ask people to prepare for a colonoscopy."

What happens during an endoscopy?

During an endoscopy, Dr. Ergun says that there is always an anesthesiologist present to give sedation via an intravenous catheter. For an upper endoscopy, a bite block is used in the patient's mouth.

"People are not awake during an endoscopy," Dr. Ergun. "It is painless, they are completely asleep, and they don't remember it. But during that time, for an upper endoscopy, we go down through the mouth. There's a little bite block to protect their teeth, and we do our thing. And if we have to do the bottom, same thing, but you don't use a bite block."

Then, the doctor performing the endoscopy will place the scope and begin the procedure. Depending on the needs of the patient, the doctor may investigate the anatomy, take tissue samples, or treat a condition by removing polyps, cauterizing blood vessels, or widening the esophagus.

How long does an endoscopy take?

Dr. Ergun says that gastroenterologists budget 30 minutes for both an upper endoscopy and a colonoscopy. A colonoscopy may only last 20 to 25 minutes, depending on a person's unique circumstances; an upper endoscopy, 15 to 20.

Other types of endoscopy completed by other medical specialties may take up to an hour or longer, depending on the part of the body being examined and whether it is being used as a screening or treatment.

Is endoscopy painful?

The biggest worry people have when being told they need to have an endoscopy is whether it's painful, Dr. Ergun says. She emphasizes that it's a safe, painless procedure.

"It's not painful because sedation works," Dr. Ergun says. "I had mine done recently; it was my third time. I don't remember anything. The only thing I remember saying is, 'Did you give me something?' And then I woke up in the recovery room. And that's what most people do. They wake up and say, 'Are you going to start?' And you're already done."

What should people expect after an endoscopy?

After both upper endoscopy and colonoscopy, Dr. Ergun shares that most patients feel fine after the procedures and are eager to get back to their normal routine.

"They're hungry," Dr. Ergun says. "They always want to decide where they're going to go for breakfast or lunch. After a colonoscopy, they might feel a little bit gassy, maybe cramping. But most people feel fine. The propofol, the sedation that anesthesia uses, is so rapidly metabolized, that most people are awake by the time they come to recovery. So they don't usually experience nausea, vomiting, feel sluggish or drunk. We still tell them they can't drive home after the procedure; someone needs to come with them or drop them off and pick them up for their safety."

Are there side effects of endoscopy?

There are few side effects from an endoscopy. Some people may feel gassy or have cramps after colonoscopy, as Dr. Ergun mentioned, or if the scope entered your intestines. People may have a sore throat or sound hoarse after an upper endoscopy, but these clear up soon after the procedure.

While extremely rare, there can be complications from an endoscopy. If you experience any of the following symptoms after endoscopy, call your doctor:

• Bleeding from the rectum that doesn't improve
• Bloody bowel movements that don't improve
• Difficulty breathing
• Feeling dizzy
• Fever
• Problems swallowing
• Severe abdominal pain
• Vomiting, and the vomit resembles coffee grounds

What after care should someone complete after having an endoscopy?

Dr. Ergun says that there's not much that someone needs to do after an endoscopy. Because of the sedation used, keeping someone around to help you as the anesthesia wears and help notice if you feel off.

"Somebody needs to be with them for a little bit, they can't drive home after the procedure," Dr. Ergun says. "They need to make sure they don't have any problems eating or drinking afterwards, they don't have any pain, and that they're able to pass gas, and they're not having any fevers. It's rare to get an infection after a procedure like this, but those are the types of things that you would be asking them and making sure that things get taken care of."