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Generic name: regadenosonre-ga-DEN-oh-son ]
Drug class: Cardiac stressing agents

Medically reviewed by Philip Thornton, DipPharm. Last updated on May 1, 2023.

What is Lexiscan?

Lexiscan is a stress agent that works by increasing blood flow in the arteries of the heart.

Lexiscan is given in preparation for a radiologic (x-ray) examination of blood flow through the heart to test for coronary artery disease.

Lexiscan may also be used for purposes not listed in this medication guide.


You should not receive Lexiscan if you have a serious heart condition such as AV block or "sick sinus syndrome" (unless you have a pacemaker).

Tell your caregivers if you have a serious side effect such as chest pain or heavy feeling, pain spreading to the jaw or shoulder, sweating, general ill feeling, wheezing or trouble breathing, slow heart rate, severe headache, seizure (convulsions), weak pulse, slow breathing, or fainting.

Before taking this medicine

You should not be treated with Lexiscan if you are allergic to regadenoson, or if you have a serious heart condition such as:

  • 2nd or 3rd degree AV block; or

  • "sick sinus syndrome" (unless you have a pacemaker).

Receiving Lexiscan may increase your risk of having abnormal heartbeats, breathing problems, heart attack, stroke, or cardiac arrest. Talk to your doctor about your specific risk.

Tell your doctor if you have recently been sick with vomiting or diarrhea, or if you have ever had:

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant.

Do not breast-feed within 10 hours after receiving Lexiscan. If you use a breast pump during this time, throw out any milk you collect. Do not feed it to your baby.

How is Lexiscan given?

Lexiscan is given as an infusion into a vein. A healthcare provider will give you this injection.

You may also be given other intravenous (IV) medications that allow blood vessels to be seen more clearly on the radiologic examination.

Your breathing, blood pressure, oxygen levels, and other vital signs will be watched closely during your stress test.

Dosing information

Usual Adult Dose for Radionuclide Myocardial Perfusion Study:

0.4 mg rapid IV injection (approximately 10 seconds) into a peripheral vein using a 22 gauge or larger catheter or needle.

Comments: Administer a 5 mL saline flush immediately after injection of this drug. Administer the radionuclide myocardial perfusion imaging agent 10 to 20 seconds after the saline flush. The radionuclide may be injected directly into the same catheter as this drug.

Use: Radionuclide myocardial perfusion imaging (MPI) in patients unable to undergo adequate exercise stress.

What happens if I miss a dose?

Since Lexiscan is given by a healthcare professional in preparation for medical testing, you are not likely to be on a dosing schedule.

What happens if I overdose?

Since this medication is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

What should I avoid while receiving Lexiscan?

Avoid drinking coffee or other beverages with caffeine for at least 12 hours before your stress test.

Lexiscan side effects

Get emergency medical help if you have signs of an allergic reaction to Lexiscan: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Tell your caregiver right away if you have:

  • severe dizziness, fast heartbeats, and warmth or a tingly feeling;

  • wheezing, chest tightness, trouble breathing;

  • weak or shallow breathing;

  • chest pain or pressure, pain spreading to your jaw or shoulder;

  • a seizure;

  • low blood pressure - a light-headed feeling, like you might pass out;

  • high blood pressure - a severe headache or pounding in your neck or ears;

  • signs of a stroke - sudden numbness or weakness (especially on one side of the body), severe headache, slurred speech, balance problems.

Common Lexiscan side effects may include:

  • trouble breathing;

  • headache, dizziness;

  • chest pain or discomfort;

  • nausea; or

  • flushing (warmth, redness, or tingly feeling).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1 800 FDA 1088.

What other drugs will affect Lexiscan?

Some medicines should not be used within 12 hours before you are treated with Lexiscan. Tell your doctor about all other medicines you use, especially:

  • aminophylline;

  • dipyridamole; or

  • theophylline.

Other drugs may interact with regadenoson, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Lexiscan only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.