A nuclear medicine bone scan is safe. It uses a small radioactive tracer giving about 5 mSv (roughly 3 years of natural background radiation), and you shouldn't experience any adverse effects. The tracer fades within hours; drinking fluids helps clear it. It's generally avoided in pregnancy. Note this is different from a DXA scan, which measures bone density and uses a far lower dose.
Key takeaways
- A nuclear medicine bone scan gives about 5 mSv and has no adverse effects.
- The tracer fades within hours; drinking fluids helps clear it.
- It's generally avoided in pregnancy — tell staff if you could be pregnant.
- It's different from a DXA scan, which measures bone density at a far lower dose.
First, a quick clarification, because two different tests are both sometimes called a “bone scan”:
- A nuclear medicine bone scan uses a radioactive tracer to show bone activity (covered here).
- A DXA scan measures bone density for osteoporosis, and uses a far lower dose.
Safety of a nuclear medicine bone scan
A nuclear medicine bone scan gives about 5 mSv of radiation — roughly 3 years of natural background radiation.[3] As with other nuclear medicine, you shouldn’t experience any adverse effects from the tracer, and reactions are very rare.[2]
The tracer clears quickly
The tracer makes you slightly radioactive for a short time, but its radioactivity fades within hours and is mostly gone within a day. You’ll be encouraged to drink plenty of fluids, which helps flush it out and lowers the dose.[1]
As a general courtesy in the first few hours, it’s sensible to limit close, prolonged contact with very young children or pregnant people — your department will advise if any specific precautions apply.[1]
Pregnancy and breastfeeding
A bone scan is generally avoided in pregnancy unless needed, and special advice applies if you’re breastfeeding, so tell the team if either could apply.[2]
Frequently asked questions
How much radiation is in a bone scan?
About 5 mSv — roughly 3 years of natural background radiation. The benefit of finding the problem usually outweighs this small risk.[3]
Will I be radioactive after a bone scan?
Slightly, and only briefly — the tracer fades within hours and is mostly gone within a day. Drinking fluids helps clear it.[1]
Is this the same as a DXA “bone scan”?
No. A DXA measures bone density for osteoporosis and uses a far lower dose with no tracer. A nuclear medicine bone scan shows bone activity (fractures, infection, cancer spread).[1]
Sources
- RadiologyInfo.org (RSNA & ACR) — General Nuclear Medicine (bone scan) — www.radiologyinfo.org/en/info/gennuclear
- RANZCR / InsideRadiology — Nuclear medicine (Cain) — www.insideradiology.com.au/nuclear-medicine/
- ARPANSA — Having a scan? A guide for medical imaging (2024) — www.arpansa.gov.au/sites/default/files/documents/2024-05/patienthandout.pdf
