What Is an Endoscopy?

An endoscopy is a procedure in which a small, flexible tube with a camera is inserted through the mouth to examine the esophagus, stomach, and duodenum (the first part of the small intestine). The images are displayed on a monitor and can be recorded or photographed for further evaluation.

Benefits of Endoscopy

• To diagnose abnormalities such as narrowing, obstruction, ulcers, inflammation, bleeding, or ruptured blood vessels.
• To obtain tissue samples (biopsy) from suspicious lesions, tumors, or cancerous areas for further examination.
• To monitor the effectiveness of medical treatment and assess whether ulcers or other conditions have healed.

Procedure on the Day of Examination

1. Present your appointment card at the Outpatient Department.
2. Change into a hospital gown and remove glasses, dentures, and valuables.
3. A local anesthetic spray will be applied to your throat three times at 5-minute intervals. You may feel numbness and a thick sensation in your throat.
4. Once on the examination bed, lie on your left side with both knees bent toward your body and bite gently on a mouthguard to protect the endoscope.
5. Your blood pressure and oxygen level will be monitored every 5 minutes.
6. The physician will insert the endoscope through your mouth and into the esophagus. You should not feel pain if you cooperate with swallowing and follow the physician’s instructions.
7. The endoscope will not interfere with your breathing. You can breathe normally throughout the procedure.
8. The examination usually takes approximately 10–20 minutes.

Possible Side Effects of Upper Gastrointestinal Endoscopy

1. Aspiration may occur and could lead to pneumonia, although this is rare. Infection is also uncommon.
2. Mild throat irritation or soreness may occur. Drinking plenty of water can help relieve the discomfort.

Preparation Before Endoscopy

1. Do not eat or drink anything for 6–8 hours before the procedure.
2. Remove any removable dentures before the examination.
3. Arrive at the hospital at least 30 minutes before your appointment to allow time for preparation.
4. Inform your physician if you have any underlying medical conditions or drug allergies.
5. It is advisable to bring a family member or companion if you feel anxious about the procedure.
6. If you require a medical certificate or reimbursement documents, please inform your physician in advance.
7. Do not wear jewelry. Wear loose and comfortable clothing that can be changed easily.

After the Endoscopy

1. Rest for approximately 1–2 hours for observation of any abnormal symptoms.
2. Do not eat or drink until the numbness in your throat has completely worn off. Once sensation returns, take small sips of water first. If choking occurs, stop drinking and wait longer.
3. Observe any saliva you spit out. A small amount of blood may be present, but if significant bleeding occurs, notify medical staff immediately.
4. Mild sore throat may occur after the procedure. Avoid hot foods and drinks. Soft or liquid foods with mild flavors are recommended for 2–3 days.
5. You may return to normal activities and exercise. However, if intravenous sedation was administered, do not drive, operate machinery, or perform tasks requiring judgment for at least 24 hours after the procedure.
6. Seek medical attention immediately if you experience severe pain in the throat, chest, or abdomen, difficulty breathing, or a high fever.

Gastrointestinal Endoscopy Center

Kasemrad Prachachuen Hospital

Tel. +66 2 910 1600 ext. 1645