PET Scan FAQ - Everything You Need To Know About PET Scans (2023)


YES – Since FDA approval was granted on May 27, 2021, for “PSMA”, PET Imaging Institute has been scheduling and performing PSMA PET Scans on a regular basis. PET Imaging Institute is currently scheduling and performing PSMA PET Scans. For more information, or to be placed on our PSMA Priority List, CLICK HERE.

Ready to schedule?

Send your prescription to: or use our PSMA Fax Hotline: (954) 607-6757.

For our PSMA PET Scan FAQ please click here to view our PSMA PET scan-specific questions and answers.

How do I prepare for a PSMA PET Scan?

Unlike other types of PET scans, there are no special preparation instructions for PSMA PET Scans. There is no need to fast, no need to avoid any specific food types, and no special need to drink ‘extra’ water to prepare for your scan. There is also no need to delay or refrain from taking your medications (take all your medications as per your normal routine). If you are diabetic, there are no special precautions needed. Take your diabetic medications and maintain your normal dietary patterns as per your doctor’s instructions.

Can I get a PET scan if I have COVID-19 or If I am showing symptoms?

During this pandemic, all three of our centers are fully operational and maintain the highest level of safety standards. In most instances, you will interact directly with only one person during your visit to our centers.

However, if you have tested positive for COVID-19 or are showing symptoms of infection, we recommend you contact your primary care doctor immediately or follow CDC guidelines for care depending on your individual risks and needs.

Our staff are trained at the time of scheduling and confirmation to interact with you to determine if it’s best that you wait prior to receiving your PET scan. Rest assured that we will be here when you are ready for your scan. Please contact us at 954-981-6668 for further information.

Is a PET scan considered an “essential” or “elective” medical diagnostic test during COVID?

About 98% of all PET scans are performed in the evaluation of cancer patients. PET scans are perhaps the most valuable diagnostic test for staging and restaging of patients known to have many different types of cancer. PET scans can also evaluate the effectiveness of treatment while undergoing chemotherapy treatments (to determine if the chemotherapy is ‘working’ or not and to allow the treating doctor to stop therapies that aren’t working, and try different therapies that might be more effective). PET scans can also be used to evaluate patients with pulmonary nodules or enlarged lymph nodes to determine the likelihood that they may be cancerous.

As such, PET scans are considered an essential service during COVID and we have remained open and fully operational throughout this pandemic.

General PET/CT Scan FAQ

How can a patient tell the difference between a NEW and OLD PET scanner? I want the best but how can I tell?

Every place says they have the most up to date scanner. How can a patient tell the difference? What questions can I ask?

PET/CT technology is constantly evolving. Some of the benefits of new technology include faster scan times, lower radiation doses to the patient, and much better image quality. What does this all mean for you, the patient and how can you tell the difference?

Let’s start with the basics. Start by asking the facility, “How long does my PET scan take?” That time has decreased over the years. If the answer is more than 15 minutes? That scanner is NOT the latest and greatest. It’s not to say that scanner is below standard of care, but it’s not the most up to date scanner. At PET Imaging Institute, our scanners average about 12 minutes per scan. This depends partly on patient height (taller patients require a little more time), and some patient have a complete scan in under 10 minutes with us. If you’ve had a PET scan at another facility before, how long did you spend on the scan table? It was probably a lot longer than 12 minutes, and this makes a big difference in patient comfort.

Next, let’s talk about radiation dose. While it’s not something you can “feel”, no one wants to receive more radiation than they need to in order to have their PET scan. If you could have a PET scan that provides better quality images using less radiation, wouldn’t you prefer that option? An easy question to ask your provider is, “How much dose do you use to perform your PET scans?” PET scans doses are typically measured in “Millicuries” or “mCi”. The higher the number, the more radiation you are receiving. Scanners that are even more than a couple of years old use doses as high as 15 to 20mCi to perform a PET scan. Others use somewhere between 12 and 15mCi. This amount of radiation is -necessary- on older scanners in order to achieve basic image quality on that PET scan equipment. At PET Imaging Institute our dose ranges are typically between 4-6mCi. That’s as much as 75% lower radiation to you.

Finally, image quality is vastly improved with more modern scanners. This item is challenging to determine on your own as a difference between scanners. However, rest assured that image quality on modern scanners is far better than on scanners even a few years older. What cell phone were you using 5 years ago? What computer or TV? Think about the advances in technology in that short time, and those same advances are packed into newer PET scanners. How does that benefit you, the patient? Better image quality means more accurate diagnoses, and ultimately more accurate treatments.

To summarize, a few questions you can ask are, “How long will my PET scan take at your facility?” and “How much dose do you use to perform your PET scan?” You want to look for a scan time of about 12 minutes (or less) and a dose of around 4 to 6 “millicuries”. If you get answers of 20-30 minutes scan time (or longer) or doses of anything over 10 “millicuries”, you are not getting the best PET scan available.

Feel free to call us today if you want to learn more about your PET scan and how we can help!


Modern PET/CT scanners are so advanced that the time for a PET scan has been significantly reduced in recent years. Although PET scans used to take an hour or more, and still take an average of 30-45 minutes on almost all PET scanners, our new and advanced scanners complete PET scans in an average of about 12 minutes. Scan time can vary slightly based upon the patient height (taller patients require a few more minutes) and some special scans, such as an Axumin PET scan for Prostate Cancer can take about 20-25 minutes to complete.

If you have any special needs that you feel may prevent you from remaining on the table for 10-12 minutes, we can still perform your PET scan. Under special circumstances, we can perform a “Fast Scan” and perform a whole-body scan in as little as one minute. Although not exactly the same as a standard scan, these Fast Scans can often provide enough basic information to allow your doctor to make decisions about your care moving forward. Please contact us if you would like any more information.

Can a PET scan be ordered “STAT” or emergently? I need mine right away. Can you help?

We understand that, as a patient, you want answers and you want them as soon as possible. At PET Imaging Institute of South Florida, we offer same day appointments and great flexibility in scheduling, with early morning, evening, and weekend appointments. In today’s medical world, you may have grown accustomed to being told there is a wait of days or weeks to have your PET scan or other diagnostic tests. For most patients, any additional wait time is virtually always related to the necessary steps to obtain insurance authorization, and those times can vary based upon which insurance carrier you have. In other instances, such as with Axumin PET/CT scans for restaging Prostate Cancer, or NETSPOT for imaging Neuroendocrine cancers, the companies only produce these ‘agents’ on certain days of the week (nationwide). When scheduling your appointment, you will be advised based upon your individual needs.

Rest assured that -all- patients who contact us to schedule an appointment are offered the earliest possible appointment times, sometimes even the same day.

Regarding the term “STAT”, that term is actually derived from the Latin word, “Statum”, meaning ‘immediately’. In medical terms, it usually implies an emergent, immediately life-threatening condition. If you are experiencing such a condition, you should call 911 or go to the nearest Emergency Room for life-saving treatment. If you or your doctor indicate “ASAP” or a similar request, we always strive to provide the earliest possible appointment for you.

Please call us at (954) 981-6668 to speak to a Medical Care Coordinator if you have further questions about scheduling your PET scan.

What is the injection used for a PET/CT Scan And Is It Safe?

The technical name of the injected material is F-18 fluorodeoxyglucose (FDG). This is very similar to glucose (normal sugar), but is special because we can image it with our PET/CT scanner. There are no known side effects or adverse reactions to FDG.

(Video) How and when should PET Scans be used? What do they show?

Will I have any reaction to the injection? Does the injection hurt?

There are no known side effects or adverse reactions to FDG. Only a single, small intravenous injection is required. While everyone has a different tolerance to small injections, most people find the process virtually pain free.


Many of our patients have diabetes, renal failure or even kidney transplants and may wonder if a PET scan or the material we inject may harm the kidneys. While the “FDG”, or sugar-material we inject is excreted by the kidneys, there is no risk to those patients with kidney disease or who may be concerned about this issue. As with many tests, drinking a little extra water after your scan helps flush the FDG out of your system and is suggested as a general post-PET scan recommendation.


Our PET scanner can accommodate patients up to 500 pounds. PET scanner design, materials and construction have advanced to such a degree that newer PET scanners can accommodate patients of larger sizes and overall weight while older PET scanners cannot. Since our GE Discovery IQ 4-ring PET/CT scanner is the newest type, we are able to accommodate patients that weigh up to 500 pounds. Our scanners are also the fastest in the region, which means shorter scan times and greater patient comfort.

The technologist is responsible for greeting you, performing the PET scan itself, obtaining the highest quality PET images possible, and of course, making sure you are comfortable throughout the entire process. Once complete, a Board certified and specialty-trained PET radiologist will view your images on a dedicated workstation, compare your images to any prior studies, generate a written report using voice transcription, and electronically transmit this report to your ordering provider.

How does a PET/CT scan differ from a CAT Scan? Do you use contrast with the CAT Scan portion of the exam?

In general terms, a CT scan only evaluates the anatomical structures of your body. PET adds vital functional information that, when combined with CT, markedly improves diagnostic capabilities. This leads to far more accurate diagnosis and staging, which ultimately results in better care.

Does Chemotherapy or Radiation Therapy interfere with a PET/CT Scan?

Chemotherapy and radiation therapy do not ‘interfere’ with the performance of a PET/CT scan. However, these therapies can certainly have an effect on the underlying disease that a PET scan is evaluating. For example, if a patient has an initial PET scan which shows the extent of disease, they may undergo chemotherapy and/or radiation therapy and then return some time later for a repeat PET scan. If all goes well, that follow-up PET scan will no longer show the disease, indicating that the treatment was a success. Therefore, chemotherapy and radiation therapy can change the results of a PET scan, but not by interfering with the process of the PET scan itself.


As with most other medical imaging tests, PET scans involve a small amount of what we call “diagnostic levels” of radiation. Your doctor has ordered a PET scan because he or she feels the benefits of the scan far outweigh any small risks associated with low levels of diagnostic “x-rays”. Also, our PET scanners are capable of obtaining very high quality scans with about 70% less radiation than any other scanner in the region, far below the national average. Therefore, if you are looking for the highest quality PET scan with the lowest radiation doses in the region, give us a call at (954) 981-6668.

Is a PET/CT scan considered therapy?

No, a PET/CT scan is a test used to diagnose disease, not provide treatment. The results of a PET/CT scan help your physician determine their treatment decisions.

Why does the scanning room feel cooler than the rest of the office?

In order for the PET/CT scanner to operate properly, it must be kept in a cool and dry environment. Because the humidity level is lower in the scan room than most people are accustomed to, it feels much cooler than the rest of the office.

Will I be injected with iodine?

No iodine or iodine-containing substances are used.

Will the injection from a PET/CT scan affect my blood glucose level?

Although FDG is very similar to glucose, the amount injected is so small it will not affect your blood glucose level.

Can you give me a sedative prior to the scan?

If you feel you require medication to relax you during your scan, you should consult your physician. We cannot provide medications to patients.

Can you provide me with oxygen while I am at your facility?

Oxygen is considered a prescribed medication and therefore we regret that we cannot provide you with oxygen while at our centers. If you are in need of oxygen during your visit with us, please bring your prescribed oxygen with you.

Can I read, use my cell phone or watch TV while I am waiting?

Believe it or not, PET/CT is so sensitive that it can even be affected by eye motion, head motion, or stimulation during the “uptake phase”, which is the time period immediately following your injection. Although this may lead to some boredom, the recommendation is for you to rest quietly in a dimly lit room during this ‘uptake phase’ after injection in order to obtain the best possible image quality.

Are family members allowed to come back with me during the procedure?

No. The PET/CT scan requires the administration of a radioactive isotope. For this reason, portions of the office are restricted and can only be occupied by the patient and the authorized medical personnel.

What does the PET/CT scan see that other scans don’t?

The PET portion of the exam assesses the metabolic function of tissues in your body, whereas most other imaging modalities assess only anatomy. By combining this functional information with CT images, the end result is an exam that is far more accurate, sensitive, and specific than virtually any other diagnostic test of its type.

What’s the difference between a PET/CT bone scan and a regular bone scan?

(Video) PET scan | How Does a PET Scan Work? | Clinical application of PET scan | #biomedicine series

There are many advantages of PET/CT bone scans over conventional bone scans. To summarize, PET/CT bone scans take a far shorter amount of time to perform and obtain much higher quality images. These images use a different injection and different imaging equipment to provide a more accurate, sensitive, and specific means of determining if bone metastatic disease may be present.

Billing/Administrative FAQ

How do I make an appointment?

You may start by Clicking Here – [Book Appointment] to see all our easy options for booking an appointment.

You may also call us at (954) 981-6668 to start the scheduling process immediately.

In addition to regular daytime hours, we offer early morning, late evening, and weekend appointments for your convenience. Call us at (954) 981-6668 to schedule your appointment for a time and day that fits your schedule.

What is “Surprise Billing” and how do I avoid it?

Surprise Billing occurs when you are told a facility is “In Network” and expect lower healthcare costs for your PET scan or other medical service, but then when the bill comes you are informed that part of that service was actually “Out of Network” and get hit with the “surprise” of unexpected high bills which -you- are then forced to pay.

In some facilities, this may mean receiving multiple bills from different providers, such as an ER doctor, Radiologist and the hospital or facility charge itself.

At PET Imaging Institute of South Florida, we offer the most honest and transparent billing practices in the area. We believe that you have the right to know beforehand what to expect when it comes to billing. Have confidence that there are no hidden charges, unknown fees or unexpected surprises. Although many aspects of billing are beyond our control, and Insurance companies may occasionally deny payment even though -they- authorized the PET scan in the first place. Our dedicated staff is always ready to directly engage Insurance carriers and work with you to reach the best possible outcome based upon your individual coverage and needs.

In your time of need, you want great quality healthcare and you deserve to know what to expect when it comes to billing. We are here to provide that for you. Give us a call at (954) 981-6668 if you would like to talk to one of us today!

I had my previous PET scan or CT scan somewhere else. Can I still come to you for my next PET scan?

Yes! It is important to have “continuing care” in that any current studies should be compared to prior studies when possible. Our staff is trained to ask you about any prior imaging you may have had. We then work with other imaging centers and offices (locally, nationally or worldwide) to obtain those images for comparison. Our radiologists will then include those comparisons within your written report.

HIPAA is an important law that was passed that literally gives you, the patient, the power to go anywhere -you- want to obtain your PET scan, other imaging, or medical care wherever you choose. Hospitals, imaging centers, and doctor’s offices are required by law to provide that information in a timely manner to give you, the patient, the power to choose.

With PET Imaging Institute of South Florida, all you need to do it tell us where you had your prior imaging, and we have many methods to easily acquire that data for comparison. PIISF contracts with Medicom, a company specifically designed to quickly and digitally transfer data from your prior facility to ours, all over the internet and in advance of your visit with us. You can even choose to upload any CD’s directly to our ‘server’ or image storage location, from the comfort of your own home! We can send you an easy link if that’s an option you prefer. Reach out to us at (954) 981-6668 to start the easy process of moving your care to PET Imaging Institute of South Florida today!

What if I have an emergency or question after-hours?

If you are experiencing an emergency, please dial 911 immediately or head to the nearest emergency room. Otherwise, please call our main number at (954) 981-6668 to receive information on after-hours assistance.

What if I have questions about paying for my scan?

All office visits are payable at the time of service. We accept cash, checks, and most major credit cards. We also accept Care Credit. If you have any further financial questions or concerns, please contact our billing team at (954) 981-6668 and they’ll be happy to help you.

Why is my insurance and ID required every time I come in?

Since we handle sensitive materials, as well as to ensure maximum patient safety, we are required by law to verify your identity prior to injecting you with the radiopharmaceutical. Without proper identification presented at the time of the examination, you will not be permitted to undergo your PET/CT scan.

Your insurance card is necessary for similar reasons, as well as for your protection against insurance fraud.

PET/CT Scan Preparation FAQ

Is there a helpful video or resource to show me how to Prepare for my PET scan?

Yes! We have created a helpful Preparation Video for just that purpose. To view the video, please click here:

Why must I fast for 4 hours prior to my PET/CT Scan? Is it important to tell the technologist if I ate within the 4 hours?

The reason we ask that you fast for a PET/CT scan is because the injection given for this procedure (called “FDG”) is based on glucose (sugar). If a patient eats before the procedure, the glucose (sugar) level in the blood may be elevated and will interfere with the uptake of the radiotracer. To make sure that the cells of the body receives the correct amount of FDG, and to improve image quality, we ask you to fast so that there is no competition with glucose (sugar) in the blood. Yes, please inform the technologist if you ate within the last 4 hours so it can be noted on the chart. ** If you are having a PET/CT Bone scan or Cardiac PET/CT scan, you do not have to be fasting. **

PET/CT scans use a sugar-based agent to provide very high quality and detailed images. In order to work correctly, our agent must distribute on its own. If you have any calories, such as sugar, within that four hour timeframe, that will compete with our agent and significantly change the results of your test. Ultimately, this could affect your diagnosis and treatment.

However, we understand that accidents happen! If for any reason you do eat or drink anything other than water within this timeframe, please let us know. We would be happy to reschedule you in order to obtain the best possible images, which will lead to better care. Call us if you have any more questions.

Do I have to limit my intake of sugar prior to the PET/CT scan?

It is important that you follow the Preparation Instructions as closely as possible to maximize the quality and benefits of your scan. One of the most important aspects is limiting sugar intake for four hours prior to your appointment. We offer early morning appointments to make this as easy as possible for you, and have a nice snack pack waiting for you upon completion of your scan for your enjoyment.


Since diabetics manage sugar differently in their body, we tailor our preparation to your unique needs. Please contact our office at (954) 981-6668 to receive preparation instructions specific to your needs.

Should I Bring My Most Recent CT Scan With Me To My Appointment?

(Video) What to expect from your PET Scan - a guide for new patients

Yes, you must bring a copy of the CT report and the CD itself.

Can I Bring My Children To My PET/CT Procedure?

For safety purposes, children must be accompanied by an adult at all times while at our facilities. If you must bring your child to your appointment, please arrange to bring an adult along to supervise your child during your exam. If you are unable to bring someone along, kindly advise a member of our staff and we will work with you to reschedule your appointment.

Can I have candy, cough drops or chew gum while I am fasting?

Except for plain water, you should not chew or consume anything else during your Preparation phase. Candy, cough drops and gum have sugar and other ingredients (even if labeled sugar free) that could affect the quality of your scan.

Why is caffeine restricted for 24 hours prior to my appointment?

Along with other factors, caffeine can alter the distribution of sugar in your body. Anything that has this effect reduces image quality, which could ultimately affect your diagnosis and treatment.

Can I drink decaffeinated coffee or soda?

Other than non-flavored water, any other drinks should not be consumed within the four hour preparation timeframe. Therefore, no coffee, even decaffeinated coffee or soda should be consumed.

Does green tea or herbal tea contain caffeine?

Almost all tea contains caffeine, as even those labeled decaffeinated may contain small amounts of caffeine, sugar or calories. Therefore, it is best to avoid tea during the preparation phase of you scan. Your best PET scan will come from drinking plain water only during your scan preparation.

Can I have alcoholic beverages the day before?

There are no restrictions regarding alcoholic beverages the day before your PET/CT scan. However, you must strictly follow our guidelines during the four hour preparation timeframe, and no alcohol or flavored beverages should be consumed during that time.

Can I smoke before a PET/CT scan?

Generally speaking, smoking does not directly affect the quality of a PET scan. If you need asssistance with quitting smoking, please follow this link:

Can I use my inhaler before a PET/CT scan?

Yes, you can use your inhaler. This will have no effect on the results of your study. If you have any other questions or concerns about any other product, please give our center a call.

Can I brush my teeth before a PET/CT scan?

Normal brushing without swallowing mouthwash or toothpaste within the four hour preparation timeframe will have no effect on the outcome of your PET/CT scan.

Can I wear deodorant before a PET/CT scan?

Deodorant will not affect the quality of your PET scan.

Can I take my medications (including pain medication) before the PET/CT scan?

You may take your normal medications, including pain medication, provided you are able to take them with plain water on an empty stomach (without food). Please consult your physician regarding any questions related to your medications.

Why am I asked to use the restroom prior to the scan?

FDG is excreted through in your urine, which collects in the urinary bladder during the waiting time after your injection. You must attempt to empty your bladder prior to the scan in order to remove the excess activity in the bladder, which improves the quality of your test.

Do I have to drink anything (dye/contrast)?

A PET/CT scan only requires a small and nearly painless injection into a vein. It is not necessary to drink any contrast, and you are not injected with any ‘contrast’ such as with MRI or diagnostic CT scans.

Can I have sex before a PET/CT scan?

Sexual intercourse does not affect the image quality of a PET/CT scan.

"After My PET/CT Scan" FAQ

Can I obtain a copy of the results?

Yes. As the patient, you have a right to have a copy of your images and written report. At the time you complete your PET scan, you will be given a CD containing all the original data from your PET scan. A short time thereafter, your written report will be generated and electronically transmitted to your doctor. If you would like a copy of your report, please call (954) 981-6668 to quickly receive your free copy of the report.

Can I drink alcohol after a PET/CT scan?

There is no restriction on drinking alcohol shortly after the scan.

Will the technologist provide me with the results of my scan?

The technologist is responsible for greeting you, performing the PET scan itself, obtaining the highest quality PET images possible, and of course, making sure you are comfortable throughout the entire process. Once complete, a Board certified and specialty-trained PET radiologist will view your images on a dedicated workstation, compare your images to any prior studies, generate a written report using voice transcription, and electronically transmit this report to your ordering provider.

How long does it take for my doctor to get a copy of the results? Who interprets the results of the PET/CT Scan?

Results will be submitted in writing to your ordering physician within 24 hours. Our Board Certified Radiologists are all specially trained in PET/CT and are responsible for the interpretation of your scan.

Will my medications be restricted following a PET/CT Scan?

After your PET/CT scan, you may resume your normal daily activities, which includes taking your medications as prescribed and directed by your physician.

Is it okay to drive after my PET/CT scan? Can I return to work?

You may resume normal activity following the scan. If your physician provided you with a sedative, follow the direction of your physician.

Will my urine change color after a PET scan?

Your urine color will not change as a result of anything related to a PET scan. For more information on urine color, please follow this link:

After my PET/CT Scan, do I still need to follow up with the other scans that were ordered by my doctor (Mammograms, Ultrasound, CTs, etc.)?

Yes. You should follow the direction of your physician regarding any other diagnostic testing that needs to be performed.

After a PET/CT scan, why is it suggested to limit contact with pregnant women and young children? How long should I avoid contact?

There is no standard rule for interacting with others following a PET/CT scan. A common principle used is “ALARA”, or “as low as reasonably achievable”. Therefore, if close contact can be avoided with those that may be more susceptible to radiation effects, such as pregnant women and infants under one year of age, this should be done for several hours after the examination.

Why do I have to sit for 45 minutes after I’m injected?

Once you are injected, the material must be given ample time to distribute in the same manner sugar distributes in your body following a meal. If we were to begin your scan too soon or too late, the effectiveness of the test could be significantly diminished.

(Video) How Does a PET Scan Work?

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(Video) PET Scan: A guide to How to Prepare for PET-CT Scan


What should you not do before a PET scan? ›

Do not eat or drink anything, except water, for 6 hours before the exam. You may drink water, as much water as you can would be helpful, until arrival. Routine medications may be taken, unless you have been instructed otherwise.

Why do you have to drink lots of water before a PET scan? ›

Drinking water is encouraged to ensure hydration for best test results. Continue to take medications as prescribed. If you are diabetic, ask your doctor about diet and medication, including withholding insulin for 4 hours prior to the exam (with the exception of an insulin pump, which is permitted).

What is the most common diagnosis for a PET scan? ›

In general, PET scans may be used to evaluate organs and/or tissues for the presence of disease or other conditions. PET may also be used to evaluate the function of organs, such as the heart or brain. The most common use of PET is in the detection of cancer and the evaluation of cancer treatment.

What can you not do after a PET scan? ›

Drinking plenty of fluid after the scan can help flush it from your body. As a precaution, you may be advised to avoid prolonged close contact with pregnant women, babies or young children for a few hours after a PET scan, as you will be slightly radioactive during this time.

How do you flush your body after a PET scan? ›

What happens after the PET scan? After your PET scan, a very small amount of radioactive sugar will remain in your body. So, be sure to drink plenty of water to help flush it out your system. You don't need to follow any special dietary restrictions or guidelines after your PET scan.

How long do you stay away from people after a PET scan? ›

The radioactive tracer gives off very small levels of radiation that go away very quickly. As a precaution, you should avoid close contact with pregnant women, babies and young children for 6 hours after the scan. You need someone to take you home and stay overnight if you've had medicine to help you relax (sedative).

Can I brush my teeth before a PET scan? ›

Can I brush my teeth before a PET/CT scan? Normal brushing without swallowing mouthwash or toothpaste within the four hour preparation timeframe will have no effect on the outcome of your PET/CT scan.

Can you drink coffee with a PET scan? ›

We prefer that you avoid anything with caffeine (coffee, tea, chocolate, or soda) within 24 hours of the test. Caffeine alters the distribution of the radiopharmaceutical throughout your body, specifically to your heart.

What can I eat for breakfast before a PET scan? ›

You will be asked to eat a low carbohydrate diet. Foods that can be eaten include: meat, hard cheese, tofu, eggs, butter and vegetables with no starch. Some foods that are NOT allowed include: cereal, pasta, milk, breads and other sugars.

What are the dangers of a PET scan? ›

During these tests, you will be exposed to small amounts of radiation. This low dose of radiation has not been shown to cause harm. For children or for other people who need multiple PET scans, CT scans, and x-rays, there may be a small potential increased risk of cancer in the future.

What cancers Cannot be detected by PET scan? ›

Though most cancers are picked up on PET CT, there are a few which do not. The most important of these would be cancer of stomach (signet cell type). In such cases performing this test would be waste. However, there are cancers which are very sensitively detected which include lymphoma, GIST, etc.

Does a PET scan show all cancers in the body? ›

PET scans must be interpreted carefully because noncancerous conditions can look like cancer, and some cancers do not appear on PET scans.

Should you rest after a PET scan? ›

In most cases, you will need to rest before and after the injection of the radioactive material. For example, if you are having a brain PET scan, you will lie quietly in a darkened room before and after the injection to make sure your brain remains relaxed and is not stimulated by light, noise or reading.

Do you feel OK after a PET scan? ›

You shouldn't experience any side effects after having a PET scan and can usually go home the same day. The results of your scan won't usually be available on the same day.

How long does it take to get the results of a PET scan? ›

When should I get my PET scan results? A radiologist with specialized training in PET scans will review the images, write a report and send it to your healthcare provider. This process usually takes 24 hours.

Should you drink lots of water after a PET scan? ›

After a PET-CT scan

Drink lots of water. It helps wash any leftover radioactive substance and dye out of your body. The scan results will be interpreted by the nuclear medicine physician and/or a radiologist, and that report will be sent to your doctor.

Why do I feel sick after PET scan? ›

PET-CT Precautions

If undergoing a combination PET-CT scan, the iodine-based contrast dye used for the CT component can cause side effects, including nausea, vomiting, headache, itching, flushing, and mild rash. In rare cases, a serious, all-body allergic reaction known as anaphylaxis may occur.

How long does a full body PET-CT scan take? ›

The scan usually takes about 15 to 20 minutes but you can expect to be in the PET imaging department for between 2 and 3 hours. Before the scan, you should: ask about any food and drink restrictions before your scan. bring any previous x-ray or radiology images you have.

Can you sleep during a PET scan? ›

Then, the patient will be asked to lie on a table that passes slowly through the scanner. The scanner resembles a CT scanner, but has a much larger opening. Some people fall asleep during the scan.

Can I take my medication before a PET scan? ›


Patient can take normal medications except for diabetic or syrup based medications. Avoid any strenuous exercise 24-36 hours prior to your appointment.

Can you wear regular clothes for a PET scan? ›

Specific protocols may vary, but generally a PET scan follows this process: You will be asked to remove any clothing, jewelry, or other objects that may interfere with the scan. If you are asked to remove clothing, you will be given a gown to wear.

How do you stay calm during a PET scan? ›

Managing Anxiety Related to Scan Results
  1. Meditate — Practicing mindfulness or meditation can help you stay calm during difficult times. ...
  2. Exercise — Exercise not only benefits your health, but also improves your mood and reduces stress.
Jun 7, 2021

What medications should you not take before a CT scan? ›

Aspirin or aspirin-containing compounds – Stop taking five days before your procedure. Plavix – Stop taking five days before your procedure. Coumadin (warfarin) – Please obtain a laboratory test (INR) before your procedure to determine the exact time to stop the medication.

Can you eat fruit before a PET scan? ›

Food that should be avoided Before PET Scan :

Fruits and Vegetables- All fruits, potatoes, corn, carrots, legumes (other beans), tomatoes, peas, squash, veggie burgers.

How much water should you drink the day before a PET scan? ›

The Day Before Your PET/CT Scan

Unless you are on fluid restriction, please drink at least eight glasses of plain water. The quality of your scan may be improved if you follow a high protein, low carbohydrate, low sugar diet during the 24 hours prior to your scan.

What happens if you eat carbs before a PET scan? ›

The radioisotope that is used in PET imaging, fluorine 18 fluorodeoxyglucose or 18F-FDG, is a glucose transporter. This radioisotope will go to any metabolically active areas in the body. If the glucose levels are elevated from food or drink the patient consumed prior to the test, the level of insulin will increase.

Can I eat peanut butter before PET scan? ›

We will provide a meal or snack for you. Beginning 24 hours before your test, follow this diet (which is a low carbohydrate diet.) Use the guideline below for menu ideas. Snacks: Celery and peanut butter, light yogurt or cottage cheese.

Can I eat a salad before a PET scan? ›

Vegetables: you may eat low-carbohydrate vegetables such as asparagus, cabbage, cauliflower, celery, chilies, cucumbers, green or wax beans, green peppers, lettuce, mushrooms, olives, onion, tomatoes, summer squash, spinach and turnips.

What is the biggest disadvantage in using a PET scan? ›

The major drawback to standard PET is that the images are of substantially lower resolution than, for example, those of CT and MRI, and PET is generally poor at delineating anatomic detail.

Does PET scan hurt kidneys? ›

Problems from the procedure are rare, but all procedures have some risk. Your doctor will review potential problems, like: Allergic reactions to the chemicals used. Kidney damage from the contrast chemical used.

Can a PET scan tell if a tumor is malignant or benign? ›

A PET/CT scan can be more sensitive than other imaging tests and may find cancer sooner than other tests do. Not all tumors take up the radiotracer, but PET/CT is highly accurate in differentiating from the benign and malignant tumors it finds, particularly in some cancers such as lung and musculoskeletal tumors.

What does it mean when lymph nodes light up on a PET scan? ›

PET scans detect the rate at which cells are using sugar. When the scan lights up brightly, it means there is metabolic activity. Most aggressive cancers light up brightly, but the caveat is inflammation in the body also lights up because inflammatory cells are also metabolically active.

What does PET negative mean? ›

In these studies, the PET result is most commonly designated as 'negative' or 'positive', wherein 'negative' is defined as having no evidence of malignant disease, with any uptake being limited to that expected for an anatomic site; and 'positive' is defined as having focal or diffuse uptake in an area incompatible ...

Can I drink coffee the day before a PET scan? ›

Don't drink caffeine for 24 hours before a PET scan of your heart. Don't do any exercise or other strenuous activity for at least 48 hours before this test.

Why can't you have caffeine before a PET scan? ›

Caffeine. Caffeine, a stimulant, can increase your heart rate and blood pressure and inhibits the effectiveness of the medication needed for the stress portion of the test. Caffeine will interfere with the results of your cardiac PET scan, and if consumed, your appointment will be rescheduled.


1. Diagnosing cancer with PET scans
(MedWatch Today)
2. A Cancer Patients Guide To Preparing for a PET Scan
(Onco )
3. How does a PET scan work?
(Imperial College London)
4. PET Scan: How To Prepare (2020)
(PET Imaging Institute of South Florida)
5. The PET Scan A Beginners Guide PETNET
(Sydney Vital)
6. What to expect during a PET scan
(I-MED Radiology Network)


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