@ShazS the tracer is the dye they inject in the canula in your arm, it makes you feel hot in the pelvis area as though you have wet yourself, and gives you a metallic taste in your mouth for a minute. They do it for most CT and bone scans and MRI, but not bone density scans.
There are various topics on here describing in detail what happens in the scan, check through the topics in recent discussions to see them.
I am very claustrophobic and have issues with my shoulders so having my arms above my head for the scan was a problem. Some ladies have had their arms by their sides, hopefully you will too.
I was heavily dosed on tranquillisers, but as you have to go away for a few hours between the first and second parts of the scan I had to top that up before the second part.
I envy you @HIT PRP here won't even give you sedatives, let alone knock you out!
In my case I was sent straight away for a bone scan and full body scan because my initial operation came back with cancer in one Sentinel Lymphnode, so they had to check if it had got out anywhere else before I started chemotherapy.
Thankfully nothing showed up, but it is interesting to read the report and see what else you have wrong with you.
Arthritis in the middle of my feet, bursitis and bone island in my hip, lung nodules, sinus changes, the list goes on. And to think I felt fairly healthy before my diagnosis!
The scan is tedious but not painful unless you have problems lying in the position you have to be for an extended length of time.