As in the link posted above, benzos (including diazepam) stay in your body for an incredibly long time after the effects have gone. Very high doses will still be in you at some level for weeks and weeks.

Quote Originally Posted by beccalous View Post
hi im new on here iv had aniety for a while but only know iv got it since jan when i got it bad due to a death in the family iv been takeing diazepam on and off since then i took a 2.5mg the other night and felt great for 24hours can a tablet last that long ?
I think it was probably that it helped you to relax a bit (or a lot!) and once you'd finally had a good chance to relax your body kept it going for you