When I hurt my back a couple of months ago, my gp prescribed paracetamol (1000mg x 4 daily), codeine (10mg x 4 daily) and ibruprofen 400mg x 3 daily),
so a codeine/paracetamol based product and ibruprofen would be fine as long as you stay within the maximum doses for each - they work on different receptors so do slightly different things - i think paracetamol/codeine is a pain reliever while ibruprofen is an inflammation reducer.
I don't think expiry of Sept '10 would make a difference tbh, most that would happen is the effect would reduce? someone else would tell you more about that i am sure.