meets all three of the proposed criteria in Criterion A.
Development and Course
Individuals whose patter n of use meets criteria for a ca ffeine use disorder have shown a
wide range of daily caffeine intake and have been consumer s of various types of caffein-
ated products (e.g., coffee, soft drinks, tea)  and medications. A diagnosis of caffeine use
disorder has been shown to prospectively pred ict a greater incidence of caffeine reinforce-
ment and more severe withdrawal.
There has been no longitudinal or cross-sect ional lifespan research on caffeine use dis-
order. Caffeine use disorder has been identi fied in both adolescents and adults. Rates of
caffeine consumption and overa ll level of caffeine consumption tend to increase with age
until the early to mid-30s and then level off.  Age-related factors for caffeine use disorder
are unknown, although concern is growing related to excessive caffeine consumption
among adolescents and young adults through use of caffeinated energy drinks. 
Risk and Prognostic Factors 
Genetic and physiological. Heritabilities of heavy caffeine use, caffeine tolerance, and
caffeine withdrawal range from  35% to 77%. For caffeine use, alcohol use, and cigarette
smoking, a common genetic factor (polysubst ance use) underlies the use of these three
substances, with 28%–41% of the heritable e ffects of caffeine use (or heavy use) shared
with alcohol and smoking. Caffeine and toba cco use disorders are associated and substan-
tially influenced by genetic factors unique to these licit drugs. The magnitude of heritabil-
ity for caffeine use disorder ma rkers appears to be similar to that for alcohol and tobacco
use disorder markers.
Functional Consequences of Caffeine Use Disorder