Hi Gavin.
Tramadol is a man made opiate and is very strong. It had a very high trading value amongst the prisoners at work, much higher than cocodamol 500/30 (contains 30mg codeine - opiate) as it gives a better high.
I would be wary about working when taking it (your GP should have made you aware of this) as it can make you pretty chilled out and care free. It can also potentially be addictive due to those qualities if taken for too long a period. Unfortunately, you also build a tolerance to it which means over time you need larger quantities to get the same 'high'. The long term heroin addicts at work (i.e opiates, like tramadol) said they took heroin to feel normal and no longer got a buzz. Scary! PS.. I worked there, I wasn't staying there
... Just reread all of that.. of course it still serves a purpose as a pain killer, and is a pretty good one for the right type of pain.