What To Do Before a Bone Density Test | Calm Scan Prep

A bone density test (often called a DXA scan) is quick and painless. You lie on a table while a scanner measures bone mineral density, often at the hip and lower spine.

Prep is light, yet a few details can trigger artifacts or a reschedule: calcium pills in the prior day, metal at the waistband, and imaging that used barium or injected contrast. This checklist shows what to do before your bone density test, from booking to check-in, so the numbers stay clean.

Start With These Steps

Use your clinic’s instructions as your main plan, then run this short check.

• Stop calcium supplements (and calcium-containing multivitamins) 24 hours before your appointment time.
• Pick clothes with no metal near the waist, hips, or lower back.
• Write down any recent barium exam, CT with injected contrast, or nuclear medicine scan, plus the date.
• Bring a simple list of medicines and supplements, even the ones you take once in a while.

What The Test Measures And Why Prep Matters

DXA uses two low-dose X-ray beams to estimate how much mineral is in your bones. A technologist positions you, the scanner passes over you, and software calculates results from the images.

Prep is mostly about avoiding false readings. Metal can block the beam. Calcium tablets sitting in the gut can appear as bright spots. Barium or injected contrast from other imaging can interfere with the picture.

What To Do Before a Bone Density Test For A Smooth Visit

When You Book: Share Recent Imaging Up Front

If you have had a barium swallow, barium enema, CT with injected dye, or a nuclear medicine scan in the past couple of weeks, tell the scheduler. These tests can leave material that affects X-ray-based images.

If you’re unsure what type of scan you had, check your portal message or discharge summary, then call the imaging center with the details.

One Week Before: Gather The Details They Will Ask For

Many clinics use a short questionnaire before a DXA scan. It may ask about past fractures, steroid medicines, menopause status, and prior bone density testing.

Set yourself up now: list your current medicines, note any fractures you have had, and write down any hip or spine surgery. Those details help the team pick the best scan sites and avoid metal hardware.

24 Hours Before: Pause Calcium Supplements And Calcium Antacids

Most centers ask you not to take calcium supplements for at least 24 hours before the exam. RadiologyInfo’s DXA scan preparation section states that same 24-hour pause.

Check labels on multivitamins and antacids. Heads-up: some antacid tablets use calcium carbonate, and that still counts as calcium. Mayo Clinic’s bone density test preparation notes the calcium pause and also flags recent barium or injected contrast as something to mention.

The Night Before: Choose Metal-Free Clothing

Wear loose, comfortable clothes with no metal near the scan area. A T-shirt and pull-on pants are a safe bet. Skip belts, jeans with rivets, and heavy zippers.

If your clinic scans the spine, avoid underwire bras. Leave jewelry at home when it sits near your chest, waist, or hips.

The Morning Of: Eat Normally And Arrive Early

Most DXA scans do not require fasting. Eat and drink as you normally would unless your clinic told you otherwise. Plan to arrive early enough for parking, check-in, and a quick questionnaire.

At check-in you may be asked your height and weight. If you have noticed height loss, mention it so the ordering clinician has it in the record.

Day-Of Safety Notes: Pregnancy, Hardware, And Pain

Tell staff before the scan if pregnancy is possible. Also mention any hip replacement, spinal fusion, or metal hardware near the hip or spine. The technologist can scan a different site if needed.

If lying flat hurts, call ahead and mention it at check-in. Padding and small positioning changes can make it easier to stay still.

If you accidentally take calcium within the 24-hour window, say so at check-in. Bring the bottle or a label photo so the team can decide whether to scan or reschedule. If you use calcium-based antacids for reflux, ask your pharmacist what to take that day instead.

Timing	What To Do	Notes
When you schedule	Tell them about recent barium or injected contrast imaging	Have dates ready if you can
7 days before	List fractures, steroid medicines, and hip or spine surgery	Bring the list or a portal screenshot
3 days before	Confirm what to stop and when	Follow your clinic’s written instructions
24 hours before	Stop calcium pills, calcium multivitamins, and calcium antacids	Check labels for calcium carbonate
Night before	Set out metal-free clothes and remove jewelry near the scan area	No zippers, snaps, or thick buckles
Morning of	Eat and drink normally unless told otherwise	Arrive early for check-in
Right before the scan	Empty pockets and remove metal items near the scan field	Coins and belts can create artifacts
Afterward	Ask when results will post and how you will get a copy	Save the report for later comparisons

What To Bring And Tell The Technologist

A DXA scan is simple, yet the report still needs context. The clearer the background details, the easier it is to scan the right sites and interpret the score.

MedlinePlus lists basic prep steps in its bone mineral density test overview, including the 24-hour calcium pause and a pregnancy reminder. Use this expanded checklist to avoid follow-up calls.

Bring These Items

• Your appointment message, plus any forms you were asked to complete.
• A current list of prescription medicines, over-the-counter products, and supplements.
• Prior DXA reports if you have them, even if they are old.
• Photo ID and insurance card if your clinic asks for them.

Tell The Technologist These Details

• Recent barium imaging or injected contrast scans, plus the dates.
• Any fractures, especially hip, spine, or wrist fractures.
• Hip replacement, spinal fusion, or other metal hardware near the scan sites.
• Current steroid use, including tablets and high-dose inhalers.
• Any limits with lying flat, bending a knee, or rotating a hip.

What Happens During The Scan

Most DXA scans measure one hip and the lower spine. You lie on your back on a padded table. A foam block may lift your legs to flatten the lower back, and the technologist may rotate your leg slightly for the hip view.

The scanner arm moves over you slowly. You will not feel anything from it, but you will need to stay still so the image stays sharp. The scanning part often takes 10 to 20 minutes, plus a few minutes for setup.

NHS patient leaflets often repeat the same prep basics: eat and drink normally, stop calcium supplements for 24 hours, and wear clothing without metal. Dorset County Hospital’s DXA scan leaflet also notes that the radiation dose is low.

Situation	What To Say	What May Happen
You took calcium inside the 24-hour window	Share the dose and the time you took it	They may scan anyway or move the appointment
Recent barium study	Share the test name and the date	They may delay the DXA until residue clears
CT or nuclear medicine with injected dye	Share the date and the body area that was scanned	Scheduling may change to avoid overlap
Hip replacement or spine hardware	Point out which side and when surgery happened	They may scan the other hip or the forearm
Pain when lying flat	Say what position you can tolerate	They can add padding or adjust positioning
Pregnancy is possible	Say so before you enter the scan room	The team may postpone or change the plan

How Results Are Reported And What They Mean

Your report usually lists a T-score for each site scanned. The T-score compares your bone density to a healthy young adult reference group. Many reports also list a Z-score, which compares you to people of the same age and sex.

Clinicians often group T-scores into ranges. A T-score of -1.0 or higher is often labeled normal. Between -1.0 and -2.5 is often labeled low bone mass (also called osteopenia). A score of -2.5 or lower is often labeled osteoporosis.

Those labels are not the full story. Fracture history, steroid use, body size, and other medical factors can change what the number means for you. Plan to review your report with the clinician who ordered the scan so your next steps match your own risk level.

After The Test: Next Moves

After the images are taken, you can get dressed and head out. A radiologist or reporting clinician reviews the scan and sends a report to the clinician who ordered it. Ask the front desk when results usually post to your portal.

Save a copy of the report in a folder you can find later. Bone density trends are easier to follow when you can line up reports across years.

Comfort And Access Tips For A Better Appointment

If you use a cane, walker, or wheelchair, bring it. Let staff know at check-in so they can plan transfers and positioning.

If you take morning pain medicine with food, stick with your normal routine unless your clinic told you otherwise. A DXA scan typically does not require fasting.

Pre-Scan Checklist To Run Before You Leave Home

Use this list the night before and again right before you head out. It is built to prevent the two most common hassles: metal surprises and calcium surprises.

• Calcium pills, calcium multivitamins, and calcium antacids paused for the full 24-hour window.
• Clothes picked: no metal zippers, snaps, buttons, or thick buckles near the scan area.
• Jewelry set aside and pockets cleared of coins and other metal items.
• Medicine and supplement list ready, plus dose details if you know them.
• Dates written down for barium imaging, CT with injected contrast, or nuclear medicine scans in the past couple of weeks.
• Prior DXA reports packed or saved on your phone for easy access.
• Pregnancy status noted if it applies, so you can tell staff before imaging begins.