IV - the amount of caffeine DV-heart rate of children to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults.
Children 1 to 2 years old: 80 to 130 beats per minute. Children 3 to 4 years old: 80 to 120 beats per minute. Children 5 to 6 years old: 75 to 115 beats per minute. Children 7 to 9 years old: 70 to 110 beats per minute
Caffeine is an imperative anxious system stimulant of methylxanthine elegance. it's far used as a cognitive enhancer, increasing alertness and attentional performance. Caffeine acts via blockading binding of adenosine to the adenosine A₁ receptor, which complements the release of the neurotransmitter acetylcholine.
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