Is it necessary to fast before a gallbladder color ultrasound?

Abdominal ultrasound of the gallbladder usually requires fasting, typically requiring 8–12 hours of禁食 before the examination. The gallbladder stores bile, and after eating, it contracts to release bile to aid digestion. At this time, the gallbladder wall becomes thinner and its volume decreases, which may affect the doctor's assessment of the gallbladder's shape, size, and any potential abnormalities. When the patient is fasting, the gallbladder is well distended, allowing for clearer visualization of the gallbladder wall, intraluminal echoes, and abnormalities such as stones or polyps. Drinking water (excluding sugary beverages) before the examination generally does not interfere with results, but consumption of solid food should be avoided.

Strict fasting is required before the examination, although small amounts of plain water may be consumed. If other upper abdominal examinations, such as of the liver or pancreas, are also required, the same fasting guidelines apply. High-fat breakfasts should be avoided on the day of the examination to prevent stimulating gallbladder contraction. If fasting is not possible due to special circumstances, inform the doctor in advance to determine whether the examination timing should be adjusted. Normal eating and drinking can resume after the examination, but patients with abnormal initial results should follow medical advice to undergo further diagnostic tests, such as CT or MRI, as needed. Maintain a low-fat diet regularly and avoid overeating. If abdominal pain persists or worsens, seek timely medical attention to determine the cause.