Pharmacologic Myocardial Perfusion Test (PNET)

Also called a Regadenoson Nuclear Stress Test

If you are not able to walk on the treadmill, then an intravenous medication will be given instead, to simulate the stress of exercise while you lie flat on a stretcher. The most common medication we use is called “Regadenoson” (or Lexiscan), and it takes about 30 seconds to administer. Some people experience minor side effects including flushing, chest tightness, and headache. These symptoms usually subside within a few minutes. Following the medication, you will lie flat on a stretcher while the nuclear camera acquires images of blood flow in your heart. As with the exercise nuclear stress test, there are two sets of images taken, to compare blood flow before and after the medication.


The test takes about three hours from start to finish. Wear (or bring) comfortable clothes. Eat a light meal about three hours before the test (do not fast!) and take your usual medications unless otherwise directed by your physician. Be sure to drink sufficient water before the test so that you will be well hydrated.


Please note that foods, beverages, and medicines that contain caffeine will interfere with the action of regadenoson, and these must be avoided for at least 12 hours prior to the test. We may need to reschedule your test if there is caffeine in your system.


Please follow these important instructions to prepare for your test:


48 hours prior to your test do not take any of the following medications:

  • Aggrenox

  • Any Ephedrine-containing medications

  • Any Theophylline-containing medications

  • Cialis

  • Dipyridamole

  • Pletal

  • Primatene

  • Trental

24 hours before your test do not take any of the following medications:

  • Anacin

  • Cafergot

  • Darvon Compount

  • Esgic

  • Excedrin

  • Fiorinal

  • Floricet

  • Levitra

  • Norgesic

  • Synalgos

  • Viagra

  • Vigromax

12 hours before your test do not eat or drink anything containing caffeine (even decaf).


Examples of caffeine-containing products include:


  • Chocolate

  • Coffee (regular and even decaffeinated)

  • Many soft drinks

  • Tea

Women who may be pregnant should inform the technologist prior to the start of the test.

Find Us

Lown Cardiovascular Group
830 Boylston Street, Suite 205
Chestnut Hill, MA 02467

Our office is easily accessible by public transportation or car, with free on-site parking and no facility fees.

Reach Us

Front Desk: 617-732-1318
Appointments: 617-732-1318
Billing: 617-732-1318


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Office Hours

Monday-Friday (except holidays)

8:00 AM to 4:30 PM