title: Anxiety and muscle tension as consequences of caffeine withdrawal.
abstract: Regular consumers of caffeine had higher muscle tension after three or more hours of abstinence than low caffeine consumers. This difference was absent after double-blind administration of caffeine citrate or placebo. In a discriminative reaction time test, caffeine treatment improved performance. Among subjects receiving placebo, anxiety was highly correlated with prior caffeine use, suggesting that even a brief abstinence may produce anxiety in the regular user.
mesh_terms: D000328:Adult; D001007:Anxiety / Q000209:etiology*; D002110:Caffeine / Q000494:pharmacology*; D006801:Humans; D009119:Muscle Contraction / Q000187:drug effects*; D013375:Substance Withdrawal Syndrome / Q000150:complications / Q000503:physiopathology*
chemical_list: D002110:Caffeine