Addiction and habituation

According to the APA, addiction is characterized by compulsive drug-taking behavior and evidence of social, psychological, medical, or occupational dysfunction.⁶⁷ Since even the heaviest users of caffeine do not meet these criteria, the APA does not recognize caffeine addiction as a classifiable disorder.⁶⁷ In fact, even though regular intake of caffeine can produce tolerance, compulsive drug-seeking behavior involving caffeine has never been observed.⁵⁸

Still, some clinicians remain concerned that caffeinated analgesics may lead to abuse. The belief is that headache patients may continue to use caffeinated analgesics, in part, to avoid caffeine- withdrawal headache.^71-73 In experimental contexts, however, this phenomenon is too inconsistent to constitute a reliably valid syndrome.⁷⁴ Moreover, studies have shown that opioid analgesics are the only class of medications CDH patients are more likely to use than episodic headache patients; there is no association between caffeinated analgesics and CDH.⁶⁰

Another concern is that people will exhibit drug-seeking behavior, using caffeinated analgesics for their stimulant properties. Even with the widespread availability of caffeine-containing beverages and over-the-counter caffeine tablets sold for alertness, reports of deliberate caffeine abuse are uncommon.⁵⁸

The symptoms of caffeine withdrawal are often confused with addiction. But some drugs produce adaptation and withdrawal effects if consumption suddenly ceases-without any evidence of abuse potential.⁵⁸ Patients taking beta-blockers, for example, sometimes develop a tolerance to their medication with regular consumption. If the patient stops taking the beta-blocker abruptly, the resulting rise in blood pressure clearly demonstrates the withdrawal effect. It appears that a similar process occurs with caffeine, and regular use appears to give rise to a non-addictive tolerance.