About Your MSK Precise™ Radiation Therapy for Prostate Cancer

Time to Read: About 21 minutes

This information will help you get ready for your MSK Precise radiation therapy to your prostate. It’ll help you know what to expect and how to care for yourself before, during, and after your radiation therapy.

Read through this resource at least once before you start MSK Precise. After that, use it as a reference in the days leading up to your treatments to help you get ready. Bring this resource to all your appointments with your radiation therapy team. You and your radiation therapy team will refer to it throughout your care.

About Radiation Therapy

Radiation therapy uses high-energy radiation to treat cancer. It works by damaging the cancer cells and making it hard for them to multiply. Your body can then naturally get rid of the damaged cancer cells. Radiation therapy also affects normal cells, but your normal cells can repair themselves in a way that cancer cells can’t.

Radiation therapy takes time to work. It takes days or weeks before cancer cells start to die, and they keep dying for weeks or months after radiation therapy ends.

Before your first radiation treatment, you’ll have a treatment planning procedure called a simulation. During your simulation, your radiation therapists will take imaging scans and mark your skin with little tattoo dots. They’ll also make a mold of your lower body. These things are done to:

  • Map your treatment site.
  • Make sure you get the right dose (amount) of radiation.
  • Limit the amount of radiation that gets to your nearby tissues.

About MSK Precise

MSK Precise is different from traditional radiation therapy. It uses a precise, high-dose form of radiation therapy called stereotactic body radiotherapy (SBRT) to deliver high doses of radiation to tumors accurately.

It’s normal for your prostate and other organs to shift slightly as you move and breathe. This can happen between and during your treatments. Before you start MSK Precise, you may have fiducial markers (tiny metal objects that are visible on imaging scans) placed in your prostate. These markers will help your radiation oncologist know exactly where your prostate is during your treatment. This helps them target high doses of radiation directly to your prostate. You can read more about the markers in the “Fiducial Markers and Rectal Spacers” section.

Your MSK Precise radiation therapy will be given in 5 treatments. This is fewer than with other types of radiation therapy because the treatment doses are stronger. MSK Precise can be used alone or along with other treatments for prostate cancer, such as brachytherapy or hormonal therapy.

Your role on your radiation therapy team

Your radiation therapy care team will work together to care for you. You’re a part of that team, and your role includes:

  • Getting to your appointments on time.
  • Asking questions and talking about your concerns.
  • Telling someone on your care team when you have symptoms related to your treatment.
  • Telling someone on your care team if you’re in pain.
  • Caring for yourself at home by:
    • Quitting smoking if you smoke. MSK has specialists who can help you quit smoking. For more information about our Tobacco Treatment Program, call 212-610-0507.
    • Caring for your skin based on your care team’s instructions
    • Drinking liquids based on your care team’s instructions.
    • Eating the foods your care team suggests.
    • Staying around the same weight.

Before Your MSK Precise Radiation Therapy

Fiducial Markers and Rectal Spacer

Before you start MSK Precise, you might have a procedure to place fiducial markers, a rectal spacer, or both.

  • Fiducial markers are tiny metal objects (about the size of a grain of rice). They help your healthcare providers line up the beams of radiation and make sure your radiation treatments are delivered exactly the same way each time. This helps them target the tumor and avoid your nearby healthy tissue. The fiducial markers will stay in your prostate after your treatment.
  • A rectal spacer is a gel called SpaceOAR® hydrogel that’s placed between your prostate and rectum (the lower end of your colon) to move them apart. This protects your rectum from radiation and reduces some side effects of radiation therapy. The rectal spacer will stay in place for about 3 months. Then, it’ll be absorbed by your body and come out in your urine (pee).

If you’re getting fiducial markers or a rectal spacer, your healthcare provider will talk with you about what to expect and give you the resource About Your Fiducial Marker and Rectal Spacer Placement.

Sperm Banking

Radiation to your prostate can affect your sperm production and ability to have biological children in the future. If you think you may want to have biological children after radiation therapy, we recommend banking your sperm before you start treatment. For more information, read Sperm Banking and Building Your Family After Cancer Treatment: For People Born With Testicles.

Bowel Preparation

You’ll need to clear extra stool (poop) from your body for your simulation and radiation treatments. This is called bowel preparation. Bowel preparation helps lower your risk of side effects by limiting the amount of radiation that gets to nearby healthy tissues and keeping your prostate in the same position during your treatments.


You’ll need the following supplies:

  • Methylcellulose dissolvable fiber supplement (such as Citrucel® powder).
  • Simethicone 125 milligram (mg) tablets (such as Gas-X® Extra Strength).
  • 6 saline enemas (such as Fleet® saline enemas).

You can buy these at your local pharmacy without a prescription.


A member of your radiation therapy team will tell you exactly when to start your bowel preparation. You’ll start at least 3 days before your simulation appointment.

  • Take 1 tablespoon of methylcellulose powder every day. Dissolve it in liquid following the instructions on the package.
  • Take 2 (125 mg) simethicone tablets the night before your simulation and treatment appointments.
  • Take 2 (125 mg) simethicone tablets about 2 hours before your simulation and treatment appointments.

Diet guidelines to minimize bloating

During your radiation therapy, gas or fluid can build up in your bowels and cause bloating. When your bowels are bloated, they can expand into the treatment area and be exposed to radiation. This can cause side effects or make your side effects worse.

Follow the guidelines below to lower your risk of bloating during radiation therapy. It’s best to start 2 to 3 days before your simulation and continue until you have finished your radiation therapy.

  • Chew your food well.
  • Limit or avoid foods that release gas when they’re digested, such as:
    • Asparagus
    • Beer
    • Broccoli
    • Brussels sprouts
    • Cabbage
    • Cauliflower
    • Corn
    • Dried beans, peas, and other legumes
    • Garlic
    • Leeks
    • Milk and other dairy products with lactose (if you’re lactose-intolerant)
    • Onions
    • Prunes
  • Avoid carbonated (fizzy) drinks, such as sodas and sparkling waters.
  • Limit or avoid sugar alcohols, such as xylitol, sorbitol, and mannitol. Sugar-free foods often have sugar alcohols. If you’re not sure, check the ingredients list on the food’s Nutrition Facts label.
  • Choose cooked vegetables instead of raw vegetables.
  • Depending on your symptoms, your healthcare provider may tell you to eat more or less fiber. Follow their instructions.

If you’re bloated, keeping a food journal can help you see which foods may be causing it. Write down your foods and drinks, the time you have them, and the time you start feeling bloated. Bring your food journal to your appointments. Your healthcare provider will use it to help you manage the bloating.

A clinical dietitian nutritionist can talk with you about your diet and help you design an eating plan that meets your needs. If you’d like to meet with a clinical dietitian nutritionist, ask your radiation oncologist or nurse for a referral.

Vitamins and dietary supplements during radiation therapy

It’s OK to take a multivitamin during your radiation therapy. Do not take more than the recommended daily allowance (RDA) of any vitamin or mineral.

Do not take any other dietary supplements without talking with a member of your care team. Vitamins, minerals, and herbal or botanical (plant-based) supplements are examples of dietary supplements.

Take devices off your skin

You may wear certain devices on your skin. Before your simulation or treatment, device makers recommend you take off your:

  • Continuous glucose monitor (CGM)
  • Insulin pump

If you use one of these, ask your radiation oncologist if you need to take it off. If you do, make sure to bring an extra device to put on after your simulation or treatment.

You may not be sure how to manage your glucose while your device is off. If so, before your appointment, talk with the healthcare provider who manages your diabetes care.

Simulation Appointment

The night before your simulation appointment:

  • Take 2 (125 mg) simethicone tablets.

The morning of your simulation appointment:

  • Take 1 tablespoon of methylcellulose powder as usual. Dissolve it in liquid following the instructions on the package.
  • Take 2 (125 mg) simethicone tablets about 2 hours before your appointment.
  • Give yourself a saline enema 2 to 3 hours before you leave for your appointment.
  • Take your daily medications as usual.

During your simulation, you’ll stay in one position for a long time. If you think this will be hard for you, take acetaminophen (Tylenol®) or your usual pain medication 1 hour before your appointment.

It’s OK to have a light meal, unless your healthcare provider tells you otherwise.

You’ll need to change into a hospital gown for your simulation. Wear comfortable clothes that are easy to take off. Don’t wear jewelry, powder, or lotion.

When You Arrive

When you arrive for your appointment, a member of your radiation therapy team will check you in. You’ll be asked to say and spell your full name and date of birth many times during your appointment. This is for your safety. People with the same or a similar name might be having care on the same day as you.

Your radiation therapists will greet you and take a photograph of your face. This picture will be used to identify you throughout your treatment. They’ll also review what to expect during the simulation. If you haven’t already signed a consent form, your radiation oncologist will review it with you and ask for your signature.

Your radiation therapists may also ask you to drink 8 to 12 ounces of water before the simulation starts. This is to fill your bladder. Having a comfortably full bladder and empty bowel during your treatments will help limit the amount of radiation that gets to your healthy tissue. This helps lower your risk of side effects.

When it’s time for your simulation, you’ll change into a hospital gown. Keep your shoes on.

During Your Simulation

Once you’re ready, your radiation therapists will help you lie on your back on the simulation table. The table will have a sheet on it, but it’s hard and doesn’t have a cushion. If you haven’t taken pain medication and think you might need it, tell your radiation therapists before your simulation starts. Also, the room is usually cool. If you feel uncomfortable at any time, tell your radiation therapists. They’ll do everything they can to make sure you’re comfortable and have privacy.

Throughout your simulation, you’ll feel the table move into different positions. The lights in the room will be turned on and off and you’ll see red or green laser lights on each wall. Your radiation therapists use these laser lights as a guide when they position you on the table. Do not look directly into the laser. If you do, it may damage your eyes.

Don’t move once your simulation starts. It’s important that you stay in the same position. If you’re uncomfortable or need help, tell your radiation therapists.

Your simulation will take about 4 hours but can be shorter or longer depending on your specific treatment plan. Your radiation therapists will walk in and out of the room during your simulation, but there will always be someone who can see and hear you. You’ll hear your radiation therapists talking to each other as they work. They’ll also talk to you about what they’re doing. Your therapists can play music for you to help pass the time.

Positioning (Mold)

Your radiation therapists will help you get into the correct position on the simulation table. Once you’re in the right position, they’ll make a mold of your lower body.

To make the mold, your radiation therapists will put a warm, flexible mesh plastic sheet over your hips and thighs and shape it to fit around your body. The plastic will form a hard mold as it cools. This procedure takes about 15 minutes.

Your radiation therapists will put the mold over you and attach it to the table for your simulation and all your treatments. This will help make sure you’re in the same exact position each time.

Imaging Scans

While you’re lying in your position, you’ll get a computed tomography (CT) scan of the area to be treated (see Figure 1). The CT scan will take about 45 minutes. During the scan, you’ll hear the machine turn on and off. Even if the noise seems loud, your radiation therapists will be able to hear you if you speak with them.

You’ll also have magnetic resonance imaging (MRI) scans of your prostate during your simulation. If you need other imaging, your radiation nurse will talk with you about what to expect.

These scans are used only to map your treatment. They are not used for diagnosis or to find tumors.

Figure 1. CT scan machine

Figure 1. CT scan machine

Skin Markings (Tattoos)

Your radiation therapists will use a felt marker to draw on your skin in the treatment area being treated. Then, they’ll make about 4 to 6 tattoos using a sterile needle and a drop of ink. Each tattoo will feel like a pinprick. The tattoos won’t be bigger than the head of a pin.

After they make the tattoos, your radiation therapists will take several photographs of you in your simulation position. The photographs and tattoos will be used to position you correctly on the table each day of your treatment.

You can wash off the felt markings after your simulation. The tattoos are permanent and will not wash off. If you’re concerned about having tattoos as part of your radiation treatment, talk with your radiation oncologist.

Scheduling Your Radiation Treatments

You’ll schedule your radiation treatment appointments before you leave your simulation appointment. MSK Precise radiation treatments are given daily or every other day from Monday through Friday. Your treatment can start any day of the week. You’ll have a total of 5 treatments.

You must come to every one of your radiation treatment appointments. Your radiation therapy may not work as well if you skip or miss treatments. If you can’t come in for a treatment for any reason, call your radiation oncologist’s office to tell your radiation therapy team. If you need to change your schedule for any reason, speak with your radiation therapists.

Treatment Planning

Between your simulation and first treatment, your radiation oncologist will work with a team to plan your treatment. They’ll use your simulation scans to carefully plan and check the angles and shapes of your radiation beams. This can take up to 2 weeks.

During Your Radiation Therapy

Radiation Treatment Appointments

The night before your treatment appointments:

  • Take 2 (125 mg) simethicone tablets.

The morning of your treatment appointments:

  • Take 1 tablespoon of methylcellulose powder as usual. Dissolve it in liquid following the instructions on the package.
  • Take 2 (125 mg) simethicone tablets about 2 hours before your appointment.
  • Give yourself a saline enema 2 to 3 hours before you leave for your appointment.
  • Take your daily medications as usual.

If pain medication was helpful during your simulation, you may also want to take it before your treatment appointments.

When you arrive for your radiation treatment appointments, a member of your radiation therapy team will check you in. Your radiation therapists may ask you to drink 8 to 12 ounces of water about 45 minutes before your treatment. This helps make sure your bladder is comfortably full during your treatment.

You’ll also change into a hospital gown. Keep your shoes on.

During Your Radiation Treatments

When it’s time for your treatment, your radiation therapists will bring you to the treatment room and help you onto the treatment table (see Figure 2). You’ll be positioned exactly how you were lying during your simulation. On the day of your first treatment, you’ll have some extra imaging scans to make sure you’re positioned correctly. This is called a set-up procedure.

You’ll also have special images (x-rays or CT scans) called beam films taken during each of your treatment appointments. These are done to make sure your position and the area being treated are correct. They are not used to see how your tumor is responding to the treatment. The beam films help your radiation therapists make sure the radiation beams are correctly lined up with your prostate.

Your radiation therapists will do everything they can to make sure you’re comfortable during your treatment. Once everything is ready, they’ll leave the room and start your treatment.

Breathe normally during your treatment, but don’t move. You won’t see or feel the radiation, but you may hear the machine as it moves around you and is turned on and off. Your radiation therapists will be able to see you on a monitor and hear you through an intercom during your whole treatment. Tell them if you’re uncomfortable or need help.

You’ll be in the treatment room for 15 to 45 minutes, depending on your treatment plan. Most of this time will be spent putting you in the correct position. The actual treatment only takes a few minutes.

Neither you nor your clothes will be radioactive during or after treatment. It is safe for you to be around other people.

Figure 2. During your treatment

Figure 2. During your treatment

Status Check Visit

Your radiation oncologist and nurse will see you at least once during your treatment to check how your treatment is going, ask about any side effects you’re having, and answer your questions. This is called a status check visit. This visit may be scheduled before or after your treatment. Plan to be at your appointment for about an extra hour on that day.

If you need to speak with your radiation oncologist or nurse any time between your treatment appointments, ask the support staff or your radiation therapists to contact them when you come in for treatment.

Side Effects of MSK Precise Radiation Therapy

Some people have side effects from radiation therapy. Which side effects and how severe they are varies from person to person. Your healthcare provider will talk with you about what to expect based on your medical history and specific treatment plan.

This section explains the most common side effects of MSK Precise radiation therapy. You may have all, some, or none of these. Most of these side effects will go away several weeks to months after you finish radiation therapy. If you have any of these side effects, your healthcare provider will give you more information and help you manage them.

Urinary Changes

Your prostate gland might swell and the lining of your bladder might become irritated. Because of this, you may:

  • Have trouble starting to urinate (pee).
  • Need to urinate more often than usual.
  • Need to urinate at night more often than usual.
  • Have sudden urges to urinate.
  • Feel a burning sensation when you urinate.

Tell your radiation oncologist or nurse if you have any urinary changes. They can recommend a change in your diet or prescribe medication that can help. You can also follow the guidelines below.

  • Drink 6 to 8 cups of water throughout the day.
  • Avoid drinking after 8 p.m.
  • Avoid foods and drinks that may irritate your bladder, such as:
    • Caffeine (such as coffee, tea, and soda).
    • Alcohol.
    • Spicy foods (especially if you feel burning when you urinate).
    • Acidic fruit juices and fruit products (such as tomatoes and tomato juice).
  • Do pelvic floor muscle (Kegel) exercises.

For more information about managing urinary changes, read Improving Your Urinary Continence.

Bowel Changes

The wall of your rectum can become irritated. After a few treatments, you may:

  • Have bowel movements (poop) more often than usual.
  • Have softer stool than usual.
  • Feel discomfort in your rectum.
  • Have mucous discharge from your anus (the opening of your rectum where stool leaves your body).
  • Have a small amount of bleeding from your rectum (for example, see bright red blood on your toilet paper or stool).
  • Pass more gas than usual.
  • Feel like you need to have bowel movements more urgently than usual.

If you have hemorrhoids, radiation therapy can make your hemorrhoid symptoms worse.

These symptoms are usually mild.

When you start radiation therapy, you can follow your usual diet. If you develop any of these side effects, talk with your radiation nurse about how to change your diet to manage them. If you’re still uncomfortable, tell your radiation oncologist or nurse. They can prescribe medication to help.

These side effects can last for about 1 to 2 months after you finish radiation therapy. Some people keep taking medications to treat urinary changes after they finish radiation therapy. It’s important to tell us if you develop side effects and keep us informed on how you’re doing.

Sexual and Reproductive Health

You can be sexually active during your radiation therapy, unless your radiation oncologist gives you other instructions. You won’t be radioactive or pass radiation to anyone else. You may have discomfort or feel a burning sensation during ejaculation. For most people, it goes away 1 to 2 months after treatment is done.

If you’re sexually active with someone who’s able to get pregnant, it’s important to use birth control (contraception) during and for 1 year after your radiation therapy. During your radiation therapy, your sperm may be damaged by the radiation. If you conceive a baby with this sperm, the baby might have birth defects. Using birth control helps prevent this.

For more information about your sexual health during cancer treatment, read Sex and Your Cancer Treatment. The American Cancer Society also has resources about sexual health issues during cancer treatment. The one for males is called Sex and the Adult Male with Cancer. You can search for it at www.cancer.org or call 800-227-2345 for a copy.

Male Sexual and Reproductive Medicine Program

MSK’s Male Sexual and Reproductive Medicine Program helps people address the impact of their disease and treatment on sexual health. You can meet with a specialist before, during, or after your treatment. We can give you a referral, or you can call 646-888-6024 for an appointment.

Skin and Hair Reactions

You probably won’t notice any changes in your skin in the treatment area, but you might lose some or all of the hair in your pubic area. The hair will usually grow back 3 to 6 months after you finish radiation therapy. The color and texture might be different.


Fatigue is a feeling of being tired or weak, not wanting to do things, not being able to concentrate, or feeling slowed down. You might develop fatigue during treatment or in the weeks after starting treatment. Fatigue can range from mild to severe and can last 6 weeks to 12 months after you finish radiation therapy.

There are a lot of reasons you might develop fatigue during treatment, including:

  • The radiation’s effects on your body.
  • Traveling to and from your treatments.
  • Not having enough restful sleep at night.
  • Not eating enough protein and calories.
  • Having pain or other symptoms.
  • Feeling anxious or depressed.
  • Certain medications, such as hormonal therapy

You might find that your fatigue is worse at certain times of the day.

Ways To Manage Fatigue

  • If you’re working and are feeling well, it’s OK to keep working. But working less may help you have more energy.
  • Plan your daily activities. Pick the things you need or really want to do and do them when you have the most energy. For example, you might go to work but not do housework or watch your child’s sports event but not go out to dinner.
  • Plan time to rest or take short (10- to 15-minute) naps during the day, especially when you feel more tired.
  • Try to sleep at least 8 hours every night. This might be more sleep than you needed before you started radiation therapy. You might also find it helpful to:
    • Go to sleep earlier at night and get up later in the morning.
    • Be active during the day. For example, if you’re able to exercise, you can go for a walk, do yoga, or visit the gym.
    • Relax before going to bed. For example, you can read a book, work on a jigsaw puzzle, listen to music, or do calming hobbies.
  • Ask family and friends to help you with things like shopping, cooking, and cleaning. Check with your insurance company to see if they cover home care services.
  • Some people have more energy when they exercise. Ask your doctor if you can do light exercise, such as walking, stretching, or yoga. Read the resource Managing Cancer-Related Fatigue with Exercise for more information. You can find it online or ask a member of your radiation therapy team for a copy.
    • Avoid riding a bicycle during your radiation treatment. Riding a bike can put pressure on your prostate area. It’s OK to use an inclined bike.
  • Eat regular meals. Your doctor may recommend following a low-fat, low-fiber diet and avoiding foods that produce gas.

If you have pain, diarrhea (loose or watery bowel movements), trouble sleeping, or feel depressed or anxious, tell a member of your radiation therapy team. They may prescribe medication or refer you to one of the following support services. You can also request an appointment by calling the numbers below.

Counseling Center
Many people find counseling helpful. MSK’s Counseling Center provides counseling for individuals, couples, families, and groups. They can also prescribe medications to help if you feel anxious or depressed.

Integrative Medicine Service
Our Integrative Medicine Service offers many services to complement (go along with) traditional medical care, including music therapy, mind/body therapies, dance and movement therapy, yoga, and touch therapy. To schedule an appointment for these services, call 646-449-1010.

You can also schedule a consultation with a healthcare provider in the Integrative Medicine Service. They will work with you to come up with a plan for creating a healthy lifestyle and managing side effects. To make an appointment, call 646-608-8550.

Many people find it helpful to join a support group. Meeting other people with cancer will give you a chance to talk about your feelings and listen to other people who have same concerns. You’ll also learn how others cope with their cancer and treatment. To learn about MSK’s support groups, visit www.mskcc.org/vp or talk with your doctor, nurse, or social worker.

After Your Treatment

Follow-up Appointments

After you finish your radiation therapy, a member of your radiation therapy team will tell you how often to see your doctor or nurse practitioner for follow-up appointments. You may have follow-up blood tests (such as PSA tests), imaging scans, or biopsies during these appointments. Keeping your follow-up appointments will also help your healthcare provider identify and treat any late side effects (side effects that happen 4 or more months after treatment).

Vitamins and dietary supplements after radiation therapy

  • You might be getting other cancer treatments along with your radiation therapy. If you are, ask the doctor managing that treatment when it’s safe to start taking dietary supplements again. Some dietary supplements are not safe to take before surgery or during chemotherapy.
  • If you are not getting other cancer treatments, you can start taking dietary supplements again 1 month after your last radiation treatment.

If you want to talk with a clinical dietitian nutritionist about your diet or supplements, tell your radiation nurse.

Urinary and Bowel Changes

Late side effects may be similar to the ones you had during treatment. There’s a very small chance you may develop other side effects. For example:

  • The opening of your bladder may become narrower.
  • You may have blood in your urine.
  • You may have bleeding from your rectum.

These side effects are rare. They may come and go over time or be persistent and chronic. Your healthcare team will help you manage them.

Even if you don’t develop any late side effects, remember that the tissues in your bladder and rectum were affected by your radiation therapy. Call your radiation oncologist if you:

  • Have any new urinary, bladder, or bowel symptoms.
  • Need to have a colonoscopy. Avoid having a colonoscopy for the first year after radiation therapy.
  • Need any type of urological or rectal procedure.

Sexual Changes

Some people develop sexual changes after finishing treatment. For example:

  • It might be more difficult or not possible to get or keep an erection. This is called erectile dysfunction (ED).
  • Your orgasms may feel different
  • When you ejaculate, the amount or thickness of your semen may be different.

These changes may happen many months or even years after radiation therapy. If you notice any of them, tell your healthcare provider. They can give you a referral to a doctor who treats these problems.


Questions to ask your radiation oncologist

Before your appointment, it’s helpful to write down questions you want to ask. Examples are listed below. Write down the answers during your appointment so you can review them later.

What kind of radiation therapy will I get?

How many radiation treatments will I get?

What side effects should I expect during my radiation therapy?

Will these side effects go away after I finish my radiation therapy?

What kind of late side effects should I expect after my radiation therapy?


Instructions Before Your Appointments

Starting 3 Days Before Your Simulation Appointment

  Instructions Purpose
Methylcellulose dissolvable fiber supplement (such as Citrucel powder)
  • Take 1 tablespoon of methylcellulose powder every day. Dissolve it in liquid following the instructions on the package.
To help you have regular bowel movements and minimize gas and bloating during your radiation therapy.
Vitamins and other dietary supplements
  • It’s OK to take a daily multivitamin, but don’t take more than the RDA of any vitamin or mineral.
  • Don’t take any other vitamins or dietary supplements without talking with your radiation oncologist.
To help your radiation therapy work its best.

Before Your Simulation and Treatment Appointments

  Instructions Purpose
Simethicone 125 mg tablets (such as Gas-X Extra Strength)
  • Take 2 (125 mg) simethicone tablets the night before your simulation and treatment appointments.
  • Take 2 (125 mg) simethicone tablets about 2 hours before your simulation and treatment appointments.
To make sure your rectum is empty.
Methylcellulose dissolvable fiber supplement (such as Citrucel powder)
  • Take 1 tablespoon of methylcellulose powder the morning of your appointments as usual. Dissolve it in liquid following the instructions on the package.
Saline enema
  • Give yourself a saline enema 2 to 3 hours before you leave for your appointments.
  • It’s OK to have a light meal unless your radiation oncologist gives you other instructions.
  • Take your daily medications as usual.
  • You may want to take acetaminophen (Tylenol) or your usual pain medication 1 hour before your appointments.
To help prevent discomfort.

Contact information

If you have questions or concerns, talk with a member of your radiation therapy team. You can reach them Monday through Friday from to

After , during the weekend, and on holidays, call 212-639-2000. Ask for the radiation oncologist on call.

Last Updated

Thursday, January 19, 2023

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