I was taking night classes and thought that smart drugs would help keep my brain functioning as if I hadn't worked all day and was mentally fatigued by the time class started. It is a rather deceptive drug. One fine day you decide that the drug doesn't work at all and stop taking it. The next morning you wake up stupid. What this means is that you can become dependent on this drug.
Drug dependency is a BAD thing.
It comes in an inhaler and you whiff it right up into your brain. You feel like you've just downed six cups of coffee. Vasopressin is actually the brain hormone responsible for making you feel mentally alert and sharp. It can also cause pretty major side effects like headaches or abdominal cramps. It can also aggravate hypertension and heart problems.