Book excerpt: Systemic medications are prescription drugs that work throughout the body. They are usually used for individuals with moderate to severe psoriasis and psoriatic arthritis. Systemic psoriasis drugs are taken by mouth in liquid or pill form or given by injection (National Psoriasis Foundation). The new edition of this book is a guide to the use of systemic drugs in dermatology bringing practising dermatologists and pharmacologists fully up to date with the latest drugs available as well as new guidelines for prescribing and monitoring established drugs. Fully revised and organised alphabetically, the book covers numerous different types of drugs and the management of their common and less common side effects. Drugs are summarised in tabular format for quick reference. The comprehensive text is further enhanced by clinical images and figures. Each chapter concludes with references and a bibliography with suggestions for further reading.