It made me totally *spaced out* and although a really good painkiller, I didn't feel safe to drive whilst taking it, all I wanted to do was lie down and sleep....
I believe I had the e/c tables - they have an enteric coating which is designed to avoid stomach irritation. If yours aren't this type, then you could ask your GP for the e/c ones instead. Anyway, you should always take them with or after food.
Incidentally, you can also get voltarol in a suppository form - slightly embarrassing at first but I found these really good at pain relief.
More info on voltarol here:-
http://www.netdoctor.co.uk/medicines/100002791 .html