This is the 20th yearly edition of Top 100 Drug Interactions, with more than 300,000 copies in print since the first edition was published in 2000. In this book the authors attempt to identify drug interactions that should not be ignored in clinical practice. Management options are given for each interaction to offer the clinician actions that may be taken to reduce the risk of an adverse outcome. The book also contains a clinically useful and comprehensive table of drugs that are substrates, inhibitors or inducers of cytochrome P450 isozymes and ABC transporters.