Amazing and powerful states of mental focus, peace, and happiness can be achieved without drugs. Such states can be maintained during everyday consciousness.

Here is some more evidence for this claim (from Mindfulness in Plain English):

One of the most memorable events in your meditation career is the moment when you first realize that you are [in] meditation in the midst of some perfectly ordinary activity. You are driving down the freeway or carrying out the trash and it just turns on by itself. This unplanned outpouring of the skills you have been so carefully fostering is a genuine joy. It gives you a tiny window on the future. You catch a spontaneous glimpse of what the practice really means. The possibility strikes you that this transformation of consciousness could actually become a permanent feature of your experience. You realize that you could actually spend the rest of your days standing aside from the debilitating clamoring of your own obsessions, no longer frantically hounded by your own needs and greed. You get a tiny taste of what it is like to just stand aside and watch it all flow past. It's a magic moment.