Preparation
How to prepare for the examination
Good preparation is as important as the examination itself. It helps the doctor see the mucosa clearly, reduces the chance of repeat testing, and improves safety. The information below is a general guide. Your final plan is chosen by the doctor according to the examination time, medicines, and health condition.
Gastroscopy
Before upper endoscopy
- The stomach must be empty. Usually solid food is stopped at least 6 hours before, and water or clear liquids about 2 hours before the examination, unless the doctor says otherwise.
- The evening before, choose light food and avoid very fatty, heavy, or late meals.
- On the day of the examination do not chew gum, smoke, drink milk, juice with pulp, or colored drinks.
- If you take blood thinners, diabetes, heart, blood pressure, or antiplatelet medicines, tell the doctor in advance. Some medicines need individual timing or temporary adjustment.
- If sedation is planned, come with an accompanying person, do not drive the same day, and avoid important decisions until fully recovered.
Colonoscopy
Before colon examination
- The quality of bowel cleansing determines the quality of the examination. Drink the laxative only according to the plan prescribed for you.
- The general approach is a low-fiber diet or clear liquids the day before, according to the doctor’s instruction. Avoid seeds, nuts, legumes, raw vegetables, and hard-to-digest food.
- On the preparation day drink allowed clear liquids: water, tea, clear broth, apple juice, or other transparent liquids. Avoid red, purple, or strongly colored liquids.
- If split dosing is prescribed, part of the solution is usually taken the previous evening and the last part on the examination day. The last dose often starts about 5 hours before and finishes at least 2 hours before.
- If the examination is in the afternoon, same-day preparation may be chosen in some cases, but only by doctor’s instruction.
- If you have kidney or heart disease, diabetes, pregnancy, previous poor preparation, long-term constipation, or take blood thinners, inform the doctor in advance.
Quality rules
What matters most
For colonoscopy, timing is especially important. Finishing preparation too early can reduce bowel cleanliness. The goal is clear yellowish output by the time of examination and enough fluid intake if you do not have fluid restriction.
Clear instruction
Read the preparation sheet several days in advance, not the night before. If any step is unclear, call and clarify.
Correct timing
The last part of the laxative should be close to the examination time but finished within the safe time advised by the doctor.
Medicine check
Discuss anticoagulants, aspirin or other antiplatelet medicines, diabetes medicines, and blood pressure medicines separately.
When to contact the doctor
- You cannot drink the solution or keep vomiting.
- There is no bowel movement several hours after the laxative.
- You have severe abdominal pain, dizziness, faintness, or marked weakness.
- You accidentally ate or drank after the forbidden time.
What to bring with you
- Previous examination results and images, if available.
- A list of all medicines with doses.
- Information about allergies and chronic diseases.
- An accompanying person if sedation is planned.