More than 85% of adults and children in the United States regularly consume caffeine, with adult caffeine consumers ingesting about 280 mg/day on average. The incidence and prevalence of the caffeine withdrawal syndrome in the general population are unclear. In the United States, headache may occur in approximately 50% of cases of caffeine absti- nence. In attempts to permanently stop caffeine use, more than 7 0% of individuals may ex- perience at least one caffeine withdrawal symptom (47% may experience headache), and 24% may experience headache plus one or more other symptoms as well as functional impairment due to withdrawal. Among individuals who abstain from caffeine for at least 24 hours but are not trying to permanently stop caffeine use, 11% may experience head- ache plus one or more other symptoms as well as functional impairment. Caffeine con- sumers can decrease the incidence of caffeine withdrawal by using caffeine daily or only infrequently (e.g., no more than 2 consecutive days). Gradual reduction in caffeine over a period of days or weeks may decrease the incidence and severity of caffeine withdrawal.
Symptoms usually begin 12—24 hours after the last caffeine dose and peak after 1—2 days of abstinence. Caffeine withdrawal symptoms last for 2—9 days, with the possibility of withdrawal headaches occurring for up to 21 days. Symptoms usually remit rapidly (within 30—60 minutes) after re—ingestion of caffeine.
Caffeine is unique in that it is a behaviorally active drug that is consumed by individ- uals of nearly all ages. Rates of caffeine consumption and overall level of caffeine con- sumption increase with age until the early to mid-305 and then level off. Although caffeine withdrawal among children and adolescents has been documented, relatively little is known about risk factors for caffeine withdrawal among this age group. The use of highly caffeinated energy drinks is increasing with in young individuals, which could increase the risk for caffeine withdrawal.
Temperamental. Heavy caffeine use has been observed among individuals with mental disorders, including eating disorders; smokers; prisoners; and drug and alcohol abusers.
Thus, these individuals could be at higher risk for caffeine withdrawal upon acute caffeine abstinence.
Environmental. The unavailability of caffeine is an environmental risk factor for incipi- ent withdrawal symptoms. While caffeine is legal and usually widely available, there are conditions in which caffeine use may be restricted, such as during medical procedures, pregnancy, hospitalizations, religious Observances, wartime, travel, and research partici- pation. These external environmental circumstances may precipitate a withdrawal syn- drome in vulnerable individuals.
Genetic and physiological factors. Genetic factors appear to increase vulnerability to caffeine withdrawal, but no specific genes have been identified.
Course modifiers. Caffeine withdrawal symptoms usually remit within 30—60 minutes of reexposure to caffeine. Doses of caffeine significantly less than one’s usual daily dose may be sufficient to prevent or attenuate caffeine withdrawal symptoms (e.g., consump- tion of 25 mg by an individual who typically consumes 300 mg).
feine withdrawal.
Caffeine withdrawal symptoms can vary from mild to extreme, at times causing functional impairment in normal daily activities. Rates of functional impairment range from 10% to 55% (median 13%), with rates as high as 73% found among individuals who also show other problematic features of caffeine use. Examples of functional impairment include be- ing unable to work, exercise, or care for children; staying in bed all day; missing religious services; ending a vacation early; and cancelling a social gathering. Caffeine withdrawal headaches may be described by individuals as ”the worst headaches” ever experienced.
Decrements in cognitive and motor performance have also been observed.