I've read a lot of Phil K Dick and can't recall this as one of his plots -- doesn't actually sound like a Phildickian story to me, more Aldous Huxley who was of course dead by then. Phil's main output of short stories was the 50s and 60s and tended to tail off after that as he concentrated on novels. (I met him in his tiny Santa Ana apartment in 1980, two years before he died. This was before the film Blade Runner which really brought him worldwide popular attention. He saw some early rough cuts of the film -- and approved them -- before he died in 1982. )
If you want a good intro to Dick, read The Man in the High Castle.