How to Fast for a Nuclear Stress Test

Your doctor likely will prescribe a nuclear stress test, also known as a thallium stress test, to look for signs of cardiac disease or damage to the heart muscle. During the stress test, you walk on a treadmill or ride a stationary bicycle to increase your heart rate. Alternatively, your doctor might opt to inject you with a medication to increase heart rate. You receive an IV with a safe, radioactive substance--thallium--which flows through your veins and shows the blood flow around your heart when viewed on an imager following the exercise. Your doctor will look for areas of the heart without thallium appearing, which indicates scar tissue from a prior heart attack (see Reference 1). An electrocardiogram monitors your heart rate while you exercise. Prior to the test, you will receive instructions to fast (see Reference 3). Follow your physician's specific fasting guidelines if they differ from the general rules below.

Things You'll Need

• Your current medications
• Comfortable clothing and shoes

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Instructions

• 1

  Do not take in any caffeinated products for at least 24 hours before the test. Avoid coffee, sodas, tea and chocolate (see Reference 2).

• 2

  Talk to your doctor about stopping medications before the test. You might have to stop heart medication, decongestants or other drugs known to affect heart rate (see Reference 3).

• 3

  The night before the test, do not eat or drink after midnight. Drink only small sips of water for taking medicine or suck on ice chips for a dry mouth (see Reference 1).

• 4

  Bring all of your regular medications and any questions for your doctor with you to the test. Talk to your doctor about any concerns before starting (see Reference 3).

• 5

  Dress in an easy-to-remove top to let the technician easily apply the electrocardiogram pads. Wear comfortable bottoms and shoes to allow for the exercise portion of the test (see Reference 3).

• 6

  Ask your doctor about resuming your normal activities after the test. Most patients can return to work immediately (see Reference 3).