You may not know, your friends might not have told you but taking caffeinated and sugary drinks with additives is dangerous before bedtime.
Although many people tolerate moderate amounts of caffeine without experiencing severe symptoms, its stimulatory affects may cause shakiness, anxiety, irritability, mood swings and sleep difficulty.

Caffeine is mildly addictive, but people who become dependent on caffeinated foods may experience symptoms of withdraw, such as headaches and lethargy.

Lethargy is a state of sluggishness and drowsy dullness. Here the mood swings when they skip usual dozes, so the caffeine addicts should cut down on its intake slowly so as to lessen withdrawal symptoms.