Update on clinically significant drug interactions in dermatology.

Although there are thousands of drug interactions (DIs) listed in computers and manuals, only about 10% are clinically significant. Equally disturbing is these systems fail to detect up to one third of all dangerous DIs. This update on clinically significant DIs is current through September 2005 and discusses systemic drugs important to dermatologists. In addition, 4 aspects of DIs are discussed that are helpful in replacing rote memory with a step-by-step, logical approach based on scientific evidence.