Answer:
The answer is stimulant use/abuse.
Step-by-step explanation:
Caffeine is a stimulant drug, as it makes people feel more alert and provides a sense of awakeness. However, because most stimulants release adrenaline in th body, in may produce a feeling of irritability when it draws off.
In reality, most of the "benefits" of stimulants are related to one's dependency on the substance. So when a person stops consuming it, the body responds in a perceived decrease of energy and attention.