The BNF provides up-to-date, practical guidance on prescribing, dispensing, and administering medicines. This essential reference reflects current best practice as well as legal and professional guidelines relating to the uses of medicines. BNF 63 has been revised and revalidated to reflect changes in product availability, emerging safety concerns and shifts in clinical practice. Some significant updates include: * Updated advice on the safe use of bowel cleansing preparations * Updated guidance on the management of stable angina and long-term prevention of cardiovascular events * Updated guidance on the management of hypertension * Updated guidance on the use and monitoring of warfarin * New advice on antiepileptic hypersensitivity syndrome * Updated advice on changing from a progestogen-only oral contraceptive to a combined oral contraceptive * Updated advice on the use of antithyroid drugs during pregnancy * Revised guidance on the risk of gastro-intestinal events with non-steroidal anti-inflammatory drugs. The BNF evaluates clinical evidence from diverse sources with information validated by a network of clinical experts and published under the authority of a Joint Formulary Committee.