Methylxanthines
is a common, naturally occurring group of stimulants. Why did I say in this way?
Caffeine, theophylline and theobromine - the active ingredients of coffee, tea,
cocoa and cola beverages are under this group. That's why I bet you must be very
familiar with this kind of stimulants although you probably may not know the
scientific term is called as methylxanthines.
The strongest and
the most effective of the above stimulants are caffeine. Caffeine produces a
clearer and quicker flow of thought and also helps to defend against drowsiness
and weariness. It can also be used to treat respiratory depression. Since caffeine
constricts blood vessels in the brain, therefore it is often used as an ingredient
in the headache remedies. However, caffeine has side effects. It may cause overstimulation,
heart palpitations, headaches and insomnia.
