Rather like a low dose of a conventional neuroleptic, books on psychopharmacology can sometimes engender a sense of mild anergia and dysphoria. The second edition of Stephen Stahl's well-received textbook has a quite opposite effect, although literary stimulants too need to be employed judiciously. Perhaps the main problem facing this literary genre is the growing scope of the field with which a psychopharmacology text might grapple. The traditional format of classificatory lists of drugs with their indications and adverse effects and a nod to acute pharmacological properties is now insufficient. The growth of neuro-science means that we need to understand the neurobiology of the brain systems with which psychotropic drugs interact. Most psychotropic drugs act on neurotransmitters, but these actions produce changes in fundamental properties of neurons, including intracellular signalling, gene expression and synaptic plasticity. Such changes have important implications for our understanding not only of drug action but also for every other kind of therapeutic intervention, including psychotherapies.

This is exciting stuff, but the application of psychopharmacology to clinical psychiatry requires practical, safe and cost-effective prescribing. The lean figure of evidence-based medicine beckons here, together with topics such as pharmacokinetics, drug interactions and toxicology. All this is probably too much for any normal-sized volume, and Stahl explicitly states in his preface that his book is written at a conceptual and not a pragmatic level. This is not a book on practical prescribing. However, on the conceptual level, particularly when describing the neurobiology of brain system and drug action, Stahl has no peer.

The opening four chapters deal with the principles of neurotransmission and expound current concepts of molecular neuropharmacology. Recent developments in second-messenger elaboration, intracellular signalling and gene expression are not all that easy to understand but I have never seen them explained better. Stahl has the verve of a true enthusiast and this, together with his experience as a practising clinician, enables him to move effortlessly between fundamental neuroscience and clinical realms of disease and drug action.

The following sections deal with psychiatric disorders and the drugs used to treat them. For a psychopharmacology textbook psychiatric syndromes are covered unusually well, which makes the book excellent value for health care professionals and academics without a postgraduate training in psychiatry. The descriptions of the pharmacology of traditional and newer psychotropic drugs are particularly clear, with ingenious linking of pharmacological properties with clinical therapeutics. The coverage extends to include drugs of abuse, cognitive enhancers and the psychopharmacology of sexual function. If you wanted to know how sildenafil citrate works but were afraid to ask, the answer (inhibition of phosphodiesterase V, which increases cyclic guanosine monophosphate thereby causing penile vasodilatation) is here.

Like its predecessor, this new edition is illustrated with numerous, accessible colour diagrams, which by themselves are sufficient to serve as a parallel text and act as valuable aids to revision (and teaching). What the book sets out to do, it does brilliantly. What practitioners will need from elsewhere is guidance on the practical art of prescribing. While this topic is not exactly neglected, some of Stahl's more innovative proposals, for example, “ California rocket fuel” (combined venlafaxine and mirtazapine) for the treatment of resistant depression, suggest that a copy of the Maudsley Prescribing Guidelines would be a reassuring companion on this exciting ride.