CAFEINE CAS : 58-08-2 - UNEP Chemicals

OECD SIDS CAFFEINE
5. TOXICITY DATE: 04-MAR-2003
SUBSTANCE ID: 58-08-2
toxic effects (tolerance and withdrawl)
14-MAR-2001 (433)
Remark: Caffeine withdrawl was examined in 12 caffeine-dependent
humans living in a residential laboratory in a 17-day
study.
Participants were maintained on caffeine (100 mg 3 times a
day), except on days 5-6 and 12-13, when caffeine was
replaced by placebo. Caffeine abstinence selectively
influenced subjective effects without altering social
behavior or performance on tasks assessing memory,
vigilance, and psychomotor skills.
toxic effects (tolerance and withdrawl)
01-MAR-2001 (434)
Remark: The effects of short-term caffeine-deprivation on mood,
withdrawl symptoms and psychomotor performance were studied
in 31 habitual coffee drinkers receiving 250 mg caffeine or
placebo. Caffeine deprivation was associated with decreased
vigor and increased fatigue and with symptoms including
sleepiness and yawing. Blood pressure was lower by 5-6
mmHg.
No changes in psychomotor performance were observed.
toxic effects (tolerance and withdrawl)
01-MAR-2001 (435)
Remark: Thirty normal children completed the single blind,
within-subject repeated-measures study with weekly sessions
to determine withdrawl effects after cessation of caffeine
intake. Subjects were evaluated with self-report measures
of symptoms and objective measure of attention, motor
performance, processing speed, and memory. During caffeine
withdrawl, there was a significant deterioration on
response time of a visual continous performance test
attention. The deterioration in response time appeared to
persist for 1 week.
toxic effects (tolerance and withdrawl)
01-MAR-2001 (436)
Remark: review on caffeine dependence. Caffeine has both positive
effects that contribute to widespread consumption of
caffeine-containing beverages and adverse unpleasant
effects
if doses are increased. Caffeine has weak reinforced
properties, but with little or no evidence for upward dose
adjustment, possibly because of the adverse effects of
higher doses. Withdrawl symptoms, although relatively
limited with respect to severity, do occur, and may
contribute to maintenance of caffeine use is not associated
with incapacitation. The positive stimulatory effects of
caffeine appear in large measure to be due to blockade of
A2A receptors that stimulate GABAergic neurons of
inhibitory pathways to the dopaminergic reward system of
the striatum.
However, blockade of striatal A1 receptors may also play a
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