Colonoscopy Bowel Preparation
Polyethylene Glycol Electrolyte Powder (Heshuang) — 2-Packet Version
⚠️ Please take note if any of the following apply to you:
- If a biopsy or polyp removal may be necessary and you are currently taking antithrombotic medications (such as aspirin, clopidogrel, warfarin, heparin, etc.), consult your doctor one week in advance to determine whether discontinuation is necessary.
- If you have symptoms of constipation (fewer than 3 bowel movements per week) or difficulty with bowel movements, follow your doctor's guidance and take an appropriate laxative 5–7 days in advance (such as polyethylene glycol 4000 or lactulose).
- If your BMI > 25 kg/m² or body weight > 80 kg, personalized bowel preparation may be necessary under your doctor's guidance (such as using the split-dose 4L polyethylene glycol electrolyte solution).
1 Dietary Preparation
⏰ 5 Days Before Examination
🚫 Prohibited: Iron supplements — they may cause darkening and increased stickiness of stool, making it difficult to pass.
⏰ 3 Days Before Examination
✔️ Permissible (Low-residue Diet): Refined rice and wheat products (white rice, plain congee, noodles), peeled and deseeded melons (such as winter melon), mashed potatoes, tofu, etc.
🚫 Prohibited (Seedy & Fibrous Foods): Dragon fruit, kiwi, watermelon, tomatoes, sesame seeds, nuts, dried fruits, etc.
⏰ 1 Day Before Examination
✔️ Permissible:
- Non-residue/Low-residue Diet: White congee, vegetarian noodles/rice noodles, boiled eggs (avoid in the final meal), lotus root powder, white bread, etc.
- Clear Liquid Diet: Clear water, clear broth, colorless sports drinks, transparent fruit juices without pulp (such as apple juice).
🚫 Prohibited:
- Colored foods and liquids — especially red or purple. Green vegetables, lean meat, coarse cereals, fruits.
- Milk, dairy products, alcohol.
2 Taking Laxatives
📋 If your examination is scheduled for the MORNING:
⏰ Day Before (8 PM)
First dose — Dissolve and drink evenly in multiple portions, completing within 1 hour. Walk around or gently massage abdomen clockwise to promote bowel movement.
⏰ 4 Hours Before Exam
Second dose — Dissolve and drink evenly in multiple portions, completing within 1 hour. Walk around or gently massage abdomen clockwise.
⏰ 2 Hours Before Exam
No liquids allowed.
📋 If your examination is scheduled for the AFTERNOON:
⏰ At Least 8 Hours Before
Finish breakfast — White congee, vegetarian noodles/rice noodles, lotus root powder, white bread, or clear liquids. Then cease all solid food intake — restrict to clear liquid diet only.
⏰ 5 Hours Before Exam
Single dose — Dissolve and drink evenly in multiple portions, completing within 2 hours. Walk around or gently massage abdomen clockwise to promote bowel movement.
⏰ 2 Hours Before Exam
No liquids allowed.
3 Precautions When Taking Laxatives
- During the bowel preparation period, consume additional water or electrolyte beverages to prevent dehydration (such as Pocari Sweat, etc.). If you experience significant abdominal bloating, vomiting, or discomfort, slow down the intake rate or temporarily suspend. Once symptoms subside, resume.
- Bowel movements may commence approximately 1 hour after taking the medication, with around 10 or more episodes. To promote comfort, gently clean the anus with wet tissue or warm water after each bowel movement.
- Readiness for the examination requires the stool to be colorless or yellowish, transparent, and free of residue, resembling a watery consistency (as illustrated in Figures 3 and 4 below). If the stool resembles Figure 1 or 2, or if it still does not meet the criteria 1 hour after consuming all preparation solution, please continue to drink more water and walk around. If you have questions, call the clinic after 8:30 AM. The total volume of laxatives consumed should not exceed 3 liters.
4 Precautions on the Day of the Examination
- You may take a small sip of water to consume chronic medications such as antihypertensive drugs, medications for hyperthyroidism, etc. For medications related to blood sugar control, please consult your doctor.
- Wear loose-fitting clothing, avoid makeup and nail polish, and refrain from bringing valuable items.
- Before the examination, remove removable dentures, glasses, and any accessories or metal items. Hand them to a companion for safekeeping.
- For painless/sedated examinations, it is mandatory to have an adult accompany you, and self-driving is prohibited.
- For female patients, schedule the examination outside of the menstrual period. If you experience fever, sore throat, fatigue, nasal congestion, or other discomfort, reschedule after symptoms subside.
📌 Important Reminder
Adequate bowel preparation is essential for the successful completion of colonoscopy. If you encounter difficulties in completing the bowel preparation, please contact us in advance.