This is an impressive book on a serious subject which at times really is a matter of life and death. It can be read by anyone interested in the pharmaceutical industry, and doesn't require any previous knowledge of medicine or even science in general.
The tone is chatty enough to keep you interested, while remaining relatively well structured. I think you will get an idea of whether you would enjoy this book by first watching either of Ben Goldacre's TED talks: if you finish watching them and think "I want to know more" then this book is going to be just the thing for you.
There is no hint of conspiracy theory in this book. Goldacre sticks to a sober recounting of the problems, and he is meticulous about backing up what he says with references, with particular emphasis on systematic reviews, which is important given the subject matter of the book. He never gets into politics, but concentrates on actual, proven real-world harms and benefits.
I also appreciate that despite the massive size of the problems he's describing, he manages to avoid despair and gives recommendations appropriate for the different sections of his readership. I thought the section on conflicts of interest was subtly thought-out and proves that Goldacre is not simply "anti-pharma" and has considered carefully how things could actually be changed in practice.
It's by no means an uplifting and easy read, but it is a fantastic book and fully worth the effort. And who knows, even if you're not a healthcare professional, you may be able to contribute to solving these problems by raising awareness.