The second edition of this textbook of clinical pharmacology is welcome in a world of evidence-based pharmacotherapy and guidelines. The key concept of the textbook continues to be the emphasis on drug benefit to risk ratio. The book is divided into three sections. Section I contains general principles, such as medicines and society, pharmacoepidemiology and drug evaluation, pharmacoeconomics, drug regulation, sources of drug information, and concepts essential to drug utilization in different populations. Section II incorporates an overview of drug classes discussed under a mechanistic point of view, providing the best possible evidence-based information on pharmacological issues. Section III is an evidence-based approach to the treatment of specific health problems. Benefits and risks of biologicals are also discussed. Finally, critical information is given on drugs that have been withdrawn in western countries, but are freely available in low income countries. Included in this section are chapters on symptomatic treatment and emergency medicine. The textbook provides a practical and useful expert guidance on patient treatment, and by offering a mechanistic description of most important drugs, it presents a basis to individualise dosages.

The textbook will be an excellent tool for optimal drug utilisation, not only by clinical pharmacologists but also by medical practitioners. This is of great importance because evidence-based pharmacotherapy and the profusion of guidelines have contributed to weaken the therapy individualisation approach. As a result, even if the benefits of drugs may have increased, the ratio benefit/risk may be decreasing. For instance, adverse drug events still account for 2.5% of estimated emergency department visits for all unintentional injuries, and for 2.1, 6.7 and 30% of hospitalisations in the paediatric, adult and elderly populations, respectively (BMJ 2004;329:15-9; JAMA 2006;296:1858-66). The incidence of drug-related deaths in university hospitals is around 0.5% (Eur J Clin Pharmacol 2002;58:479-82). It is distressing that 33% of adverse drug effects are still associated to warfarin, insulin and digoxin (Ann Int Med 2007;147:755-65). Approximately half the adverse effects reported are preventable. The cost of adverse drug effects to society is colossal, e.g. close to one billion $/year for a population of 60 000 000 (BMJ 2004;329:15-9).

Evidence-based pharmacotherapy provides a succinct appreciation of the benefits of a drug, but rarely takes into account the patient's quality of life. For instance, intensive statin therapy is recommended because it reduces the incidence of cardiovascular death (odds ratio 0.86), myocardial infarction (odds ratio 0.84), and stroke (odds ratio 0.82); however, the increased risks for any adverse event (odds ratio 1.44), for abnormalities on liver function testing (odds ratio 4.48), for elevations in CK (odds ratio 9.97) and for adverse events requiring discontinuation of therapy (odds ratio 1.28) are less often taken into account by the prescriber. This example emphasises that individualisation is of the utmost importance to keep an acceptable benefit/risk ratio (Clin Ther 2007;29:253-60). The benefits of evidence-based pharmacotherapy may be obtained whenever concordance/compliance of the patient is adequate. However, concordance rate is slightly higher than 30% for chronic conditions, such as hypertension (Curr Hypertens Rep 2007;9:184-9), indicating that the patient has to be educated about the use of drugs, and therapy has to be individualised.

Evidence-based pharmacotherapy and guidelines alone cannot solve the problems highlighted above, since individualisation, the risk of medication, as well as quality of life are insufficiently taken into account. Rational drug individualisation is required and the textbook will be a practical and easy tool to achieve this goal.

Montréal, December 2007

Patrick du Souich, MD, PhD, Chairman, Division of Clinical Pharmacology, International Union of Basic and Clinical Pharmacology