After finishing this chapter, students should be able to understand:
The ancient plants coffee, tea, and cacao all contain caffeine and two related xanthines.
Caffeine is also contained in soft drinks and nonprescription medicines.
Caffeine has a longer-lasting effect than many people realize.
Caffeine exerts a stimulating action in several brain regions by blocking inhibitory receptors for adenosine.
In regular caffeine users, headache, fatigue, or depression can develop if caffeine use is stopped.
Caffeine is capable of reversing the effects of fatigue on both mental and physical tasks, but it might not be able to improve the performance of a well-rested individual, particularly on complex tasks.
Excessive caffeine consumption, referred to as caffeinism, can produce a panic reaction.
Daily use of large amounts of caffeine increases the risk of heart attack.
