Does an ultrasound need preparation?

Asking whether an ultrasound needs preparation usually means asking about one specific exam, since the word covers many of them. This page keeps the general answer apart from the exam-specific one.

The answer

medlineplus.gov states: "Preparations for an ultrasound exam depend on what part of your body is being checked."

There is no single instruction that fits every scan. The body part being checked decides what, if anything, a patient is told to do beforehand.

Matching the exam to the condition

A scan ordered for a suspected clot and a scan ordered for peripheral artery disease are different questions. The NHLBI diagnosis page for venous thromboembolism and the NHLBI diagnosis page for peripheral artery disease show which condition each testing path belongs to, which helps a reader ask the right question about their own exam.

The follow-up question

To learn what applies to your appointment, ask the office that books the scan which body part is being checked and what that means for the day of the exam.