MRI preparation depends on the type of scan, the area of your body being scanned, and whether the scan requires contrast dye. It’s important to discuss prep with your doctor beforehand.
In rare, urgent cases, some people may have an MRI on the same day as an initial doctor’s visit. Typically, though, a doctor will schedule an MRI several days or weeks (or even months) in advance.
There usually isn’t much preparation needed for an MRI. But depending on the type of MRI you’re having and which part of the body the doctors are scanning, you may have specific instructions.
Here’s what you need to know so that you and the imaging team can be prepared for the procedure to ensure your safety and the most accurate scans.
At least 1 week before your MRI scan, you’ll want to connect with your imaging team to see whether there are any special considerations. Factors to discuss with your doctor include:
- Metal objects in your body: Tell the doctor if you have any metal parts, such as artificial joints, surgical clips, pacemakers, or cochlear implants. Also consider any metal fragments, like shrapnel from bullet wounds.
- Claustrophobia: Let the doctor know if enclosed spaces make you anxious. They may arrange for sedation on the day of the scan or provide you with a prescription to take in advance.
- Medications: Give them a list of all the medications you’re taking. The doctor will let you know if you need to make any adjustments prior to the scan.
- Allergies: Let your medical team know if you have had any allergic reactions to contrast dye from a previous procedure.
- Tattoos: Some tattoo inks may contain metal. Discuss the potential side effects with your doctor.
- Braces: If you have orthodontic braces, they might distort an MRI scan of your head. This depends on the type of braces you have, according to a 2022 study.
The facility performing the MRI may give you an intake questionnaire. Be sure to answer honestly so they can make any necessary accommodations.
MR enterography and colonography
If you’re having an MRI of your bowels, you may need to undergo bowel preparation. This may involve:
- switching to a low residue diet 3 to 5 days before your scan
- switching to a clear liquid diet 1 day before your scan
- taking a laxative, enema, or suppository to clear your bowels within a specified number of hours before your scan
- fasting for 4 to 6 hours before your scan
Instructions for bowel preparation can vary considerably, so it’s best to follow your doctor’s instructions.
Most people don’t need to do much the day before their MRI.
If you’re having a bowel MRI, you may need to continue with bowel prep.
In some cases, you may need to fast for 4 to 6 hours before your MRI. The exact timing may vary, so follow your doctor’s guidance. Fasting is typically required if you’re having:
- an abdominal MRI
- MRI enterography or colonography
- a cardiac MRI
- an MRI with contrast dye
During your fast, you can’t eat any solid food and can only drink water. You should also avoid smoking or chewing gum.
Tip
While you can drink water during your fast, be mindful of how much you drink, especially as you get closer to your MRI. You won’t be able to use the restroom during the scan, so you’ll want to limit your intake.
You’ll want to use the restroom immediately before your scan. You won’t have the opportunity to do so again until after the scan.
Wear loose, comfortable clothing to your appointment. Don’t wear anything with metal in it. That includes:
- jewelry or piercings
- hair clips
- buttons, zippers, or other fasteners
- bras with metal wiring
Some locations may have you undress and change into a gown.
Let the imaging team know if too much noise bothers you. Some places can provide headphones or offer to play music.
While older research found that children may experience anxiety during an MRI, research from 2021 suggests that children are less anxious about the experience than adults.
Still, for young children especially, you can take steps to make the first experience more comfortable, such as:
- explaining what they’ll see, hear, smell, taste, and feel during the test
- reassuring them that the machine is noisy but harmless
- bringing a comfort item, like a blanket or plush toy with no metal parts
Your child will need to lie still during the entire scan. Talk with your child’s doctor about whether they may need to use sedation or Velcro straps to help. In these cases, it can help to prepare your child for this as well.
MRI scans typically take 15 to 90 minutes but can last up to