Caffeine, an adenosine antagonist, is the most widely used mood-altering drug in the world. Caffeine is rapidly absorbed and distributed throughout the body with peak plasma concentrations typically reached 30-45 min after ingestion. The average half-life of caffeine is 4-6 h. Genetics account for some of the variability in responses to caffeine and individual differences in caffeine pharmacokinetics. Caffeine can function as a reinforcer and produces a wide range of physiological, behavioral, and subjective effects, including anxiety, insomnia, diuresis, alertness, and enhancement in some types of performance. Regular caffeine consumption can produce tolerance, withdrawal, and a substance dependence syndrome.
|Original language||English (US)|
|Title of host publication||Encyclopedia of Human Nutrition|
|Number of pages||7|
|State||Published - Jan 1 2012|
ASJC Scopus subject areas