I had a horrible experience working on New Years Day this year after a massive New Years Eve. I'd eaten a ridiculous amount of lollies over 15 hours and had been smoking weed constantly aswell. Time had flown by so quickly I didn't even realise that I wasn't going to be able to sleep before my shift so, in my munted state, I decided to get more fucked up prior to the shift instead of coming down. I took a few more pills, about 10mg of diazapam and 700mg of Lyrica. The entire shift was an utter joke, I was caught half asleep in a theatre (I work in a cinema), making coffees for customers that didn't even exist and even having a full blown conversation with a cardboard cut out of Liam Neeson. Looking back I find the situation funny but realistically I'm damn lucky I wasn't fired and I will certainly never go on a bender before a shift ever again.
I do, however, regularly smoke weed before a shift.