An endoscopy is a procedure where the inside of your body is examined using an instrument called an endoscope.

An endoscope is a long, thin, flexible tube that has a light source and camera at one end. Images of the inside of your body are relayed to a television screen.

Endoscopes can be inserted into the body through a natural opening, such as the mouth and down the throat, or through the bottom.

An endoscope can also be inserted through a small cut (incision) made in the skin when keyhole surgery is being carried out.

This page covers:

When an endoscopy is used

What happens during an endoscopy

Risks

When an endoscopy is used

An endoscopy can be used to:

  • investigate unusual symptoms
  • help perform certain types of surgery

An endoscope can also be used to remove a small sample of tissue for further analysis. This is known as a biopsy.

Investigating symptoms

An endoscopy might be recommended to investigate the following symptoms:

If the gullet (oesophagus), stomach or first part of the small intestine needs to be examined, it's known as a gastroscopy

If the bowel needs to be examined, it's known as a colonoscopy. Watch a video about what happens during a colonoscopy.

Other types of endoscopies used to investigate symptoms include: 

Therapeutic endoscopy

Modified endoscopes with surgical instruments attached to them or passed through them can be used to carry out certain types of surgery.

For example, they may be used to:

Laparoscopic surgery

A laparoscope is a type of endoscope used by surgeons as a visual aid when carrying out keyhole surgery (laparoscopic surgery).

Only small incisions are made during laparoscopic surgery, which means it's less painful afterwards and you'll recover more quickly.

Common types of keyhole surgery include:

Laparoscopies are also often used to investigate certain symptoms and help diagnose many different conditions.

What happens during an endoscopy

Endoscopies are usually carried out at local hospitals, although some larger GP surgeries may also offer the procedure.

Before having an endoscopy

Depending on what part of your body is being examined, you may be asked to avoid eating and drinking for several hours beforehand.

You may be given a laxative to help clear stools from your bowels if you're having a colonoscopy to examine the large intestine or a sigmoidoscopy to examine the rectum and lower part of the bowel.

In some cases, you may also need antibiotics to reduce the risk of an infection.

If you're taking a medicine to thin your blood, such as warfarin or clopidogrel, you may need to stop taking it for a few days before having an endoscopy. This is to prevent excessive bleeding during the procedure.

However, don't stop taking any prescribed medicine unless your GP or specialist advises you to do so.

The endoscopy procedure

An endoscopy isn't usually painful, and most people only experience some mild discomfort, similar to indigestion or a sore throat.

The procedure is usually carried out while you're conscious. You may be given a local anaesthetic to numb a specific area of your body. This may be in the form of a spray or lozenge to numb your throat, for example.

You may also be offered a sedative to help you relax and make you less aware of what's going on around you.

The endoscope will be carefully inserted into your body. Exactly where it's inserted will depend on the part of your body being examined.

For example, it may be inserted into your:

  • throat
  • anus  the opening stools are passed out of the body through
  • urethra  the tube urine passes through out of the body

If you're having keyhole surgery (laparoscopy), the endoscope will be inserted into a small incision your surgeon makes in your skin.

An endoscopy usually takes between 15 and 60 minutes, depending on what it's being used for. It will usually be carried out on an outpatient basis, which means you won't have to stay in hospital overnight.

Wireless capsule endoscopy

A wireless capsule endoscopy is a relatively new type of endoscopy. It involves swallowing a capsule that's able to wirelessly transmit images of the inside of your stomach and digestive system.

The capsule is the size of a large pill and leaves your body naturally when you go to the toilet.

It's often used to investigate internal bleeding in the digestive system when there's no obvious cause.

There are some complications associated with wireless capsule endoscopy. Swallowing the capsule can be difficult, as can passing it naturally. The capsule can also get caught in the narrow areas of your bowel, causing a blockage.

After an endoscopy

After having an endoscopy, you'll probably need to rest for about an hour until the effects of the local anaesthetic or sedative have worn off.

If you decide to have a sedative, a friend or relative will need to take you home after the procedure.

If you've had a cystoscopy to examine your bladder, you may have blood in your urine for 24 hours afterwards. This should settle, but contact your GP if you still notice it after 24 hours.

Risks 

An endoscopy is usually a safe procedure, and the risk of serious complications is very low.

Possible complications include:

  • an infection in a part of the body the endoscope is used to examine – this may require treatment with antibiotics
  • piercing or tearing (perforation) of an organ, or excessive bleeding – you may need surgery to repair tissue or organ damage; sometimes a blood transfusion may also be needed

Sedation

Sedation is usually safe, but it can occasionally cause complications, including:

When to seek medical help

Contact your GP if you notice any signs of infection in the area where the endoscope was inserted.

Signs of infection include:

  • redness, pain or swelling
  • a discharge of fluids or pus
  • a high temperature (fever) of 38C (100.4F) or above

Other signs of a possible complication after having an endoscopy include:

Contact your GP or visit your nearest accident and emergency (A&E) department immediately if you notice any of these signs and symptoms.

Page last reviewed: 11/10/2016

Next review due: 11/10/2019