Intoxication is not always visible: an unrecognized prevention challenge.
T HE USE OF alcohol or other drugs (AOD) to alter consciousness and produce intoxication is not new. Alcohol, for example, is the most widely used and abused drug on earth and has been consumed for its intoxicating effects for thousands of years. One consequence of AOD intoxication is impaired driving. One of the challenges facing prevention specialists is that many factors contribute to intoxication as well as to whether a person is ‘‘visibly intoxicated.’’ ‘‘Visible intoxication’’ (meaning a series of perceptible acts and behaviors consistent with gross impairment) is, in some cases, different from ‘‘obvious intoxication,’’ a term used in some state statutes (and some older studies to mean visibly intoxicated), that relates to a combination of all the factors used to determine whether a person is or is likely to be alcohol impaired. ‘‘Intoxication’’ is not always visible even to trained observers. The goals of this review are (i) to educate prevention specialists about the state of knowledge in determining intoxication, (ii) to provide an authoritative treatise on the subject of visible intoxication, and (iii) to address the medicolegal consequences of such intoxication—primarily the prevention of impaired driving. Historically, most of the direct consequences of intoxication have been limited to individual drinkers who, if they lived long enough, would eventually incur significant medical consequences (Brick, 2008). However, the introduction of motor vehicles and the eventual proliferation of mechanized transportation dramatically changed society. No longer were the effects of alcohol overuse limited to the drinker, but now others (passengers, occupants of other vehicles, and pedestrians) were included as well. Today about 14,000 alcohol-related fatal crashes occur per year (Yi et al., 2006). The actual number of crashes directly due to intoxication is probably lower as most recent epidemiological studies of this type include drivers with blood alcohol concentrations (BACs) of more than zero, and statistical methods, such as intupation, assume intoxication based on driver and crash profiles. But even when objective blood alcohol evidence is missing (US Department of Transportation ⁄National Highway Traffic Safety Administration, 2002), drunken driving is a major health hazard. Diverse approaches have been applied to prevent drunken driving (Hingson et al., 1996a,b, 1999; Holder et al., 2000; NIAAA, 2000) but only three approaches specifically relate to identifying signs of alcohol intoxication: DWI laws, dramshop ⁄ related host liability, and Alcohol Beverage Control Board laws. A review of differences between DWI-related issues and visible intoxication (the focus of dram shop laws) is important to the general public’s awareness and understanding of this problem, and the reduction of motor vehicle and other injuries due to intoxication. In this article, we review the development, scientific foundation, implications, and interrelationships among these approaches.