Special Note to Readers

The contributors, reviewers, editors, and publisher have made extensive efforts to ensure that the information is accurate and conforms to the standards accepted at the time of publication. However, constant changes in information resulting from continuing research and clinical experience, reasonable differences in opinions among authorities, unique aspects of individual situations, and the possibility of human error in preparing such an extensive text require that the reader exercise judgment when making decisions and consult and compare information from other sources. In particular, the reader is advised to discuss information obtained from this website with a doctor, pharmacist, nurse, or other health care practitioner.