PET Scan Preparation

There are two types of PET scans. One is used primarily for cardiac exams--this one is referred to as Myocardial Perfusion PET (also called Adenosine or Rubidium PET). The other PET exam is used to study such things as tumors, brain disorders, or infection; however, it can also be used to study the heart--this exam is referred to as FDG PET.

The required preparations for the two types of PET are very different.

If you are unsure which exam you are receiving, please call our scheduling department at: 310.423.8000 (option 1).

Myocardial Perfusion PET (also known as Rubidium or Adenosine PET)

If you are unsure if this is the correct preparation for your exam, please call our scheduling department at: (310) 423-8000 (option 1).


Exam time: approximately 3-4 hours.

FDG PET is used for tumor detection and to diagnose brain disorders or infections. It is also used for a study of the heart called myocardial viability. There is a different PET scan available, which is used to perform an exam called Myocardial Perfusion PET or Rubidium PET--the preparation for Rubidium PET is very different than for an FDG PET (please see above). 

FDG PET scans require careful preparation, so please follow instructions carefully.

Before Your Study

* Diabetics should discuss the preparation with their physician before making any alteration to their diet.

  • 48 hours before your appointment:

    • Do not do any strenuous exercise or deep-tissue massage.
  • 24 hours before your appointment:

    • Stay on a VERY LOW-carbohydrate, NO-sugar diet. Please see Low-Carbohydrate Diet Guidelines below.
    • Do use chewing gum or mints.
  • 6 hours before your appointment:

    • Do NOT eat anything with the exception of water.
    • Drinking water is encouraged to ensure hydration for best test results.
    • Continue to take medications as prescribed.
    • If you are diabetic, please consult your doctor for questions regarding diet and medication. Carefully monitor and control your blood sugar the 48 hours before the scan.

Low-Carbohydrate Diet Guidelines:

Foods allowed:

  • All meats and poultry
  • Hard cheeses
  • Non-starchy vegetables, such as: broccoli, spinach, green beans.
  • Nuts and unsweetened peanut butter
  • Diet soda and zero-calorie drinks. (Be careful to avoid caffeinated and decaffeinated drinks. Decaffeinated drinks still contain small amounts of caffeine.)
  • Tofu
  • Eggs
  • Oil, margarine, butter
Foods NOT allowed: 
  • No cereals
  • No pasta
  • No dry beans
  • No fruit and fruit juices
  • No sugar, honey, desserts, or candy
  • No starchy vegetables, such as: peas, corn, potatoes
  • No alcohol
  • No nutritional shakes or smoothies
  • No breads
  • No rice
  • No gravies
  • No jams and jellies
  • No milk or yogurt (including non-dairy milk)
  • No coffee or tea (nothing with caffeine.)

During Your Study

  • Upon arrival, the technologist will explain your procedure and answer any questions you may have.
  • You will receive an intravenous injection (in your vein) of a tracer dose of radioactive material.
  • The level of radioactivity is extremely low and has no side effects.
  • You will be asked to wait approximately 1-2 hours before the scan begins.
  • Your scan will take approximately one hour.
  • During that time you will be required to lie flat on your back, without moving.
  • Using a special nuclear medicine scanner, pictures of your body will be obtained. The scanner does not produce any radiation; it simply detects and records the distribution of the radioactive material in your body.

After Your Exam

  • There are no post-exam instructions.
  • Your study will be reviewed by an imaging physician specialist and the results sent to your physician. Your physician will discuss these results with you and explain what they mean in relation to your health.
  • To request a copy of your report, call (310) 423-8000. 

The S. Mark Taper Foundation Imaging Center provides a full range of advanced imaging, both radiology and cardiology, as well as interventional radiology and interventional tumor (oncology) treatments to the greater Los Angeles area, including Beverly Hills, Encino, Mid-Cities, Sherman Oaks, Silver Lake, Studio City, Toluca Lake, and West Hollywood.  

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