Ultrasound · Patient guide
Ultrasound Preparation: Do You Need to Fast or Have a Full Bladder?
By Clarus Magnus Health & Diagnostics · Published
One ultrasound appointment may need fasting; another may need a full bladder. The difference comes from the body part and the approach used to examine it.
Why might fasting be requested?
Some abdominal examinations have food and drink restrictions to improve the view of the structures being assessed. The centre should tell you the required interval and whether you may take medicines or small amounts of water.
Why might a full bladder be needed?
Certain pelvic examinations use a filled bladder to help obtain images. Other approaches have different requirements. Ask how much to drink, when to drink it and whether you should avoid passing urine before the scan.
What if you have a medical condition?
Tell the team if you have diabetes, a fluid restriction or difficulty holding urine. Do not force a generic preparation routine when it conflicts with your medical advice.
Read about ultrasound at Magnus and contact the team for the instructions linked to your referral.
Before travelling, confirm three things: the exact scan name, your food and drink instructions and the arrival time. If you could not complete the preparation, call and explain rather than guessing whether to cancel or proceed.
References and further reading
General patient information. Your clinician and imaging team will advise you about your individual examination.