Scenario (Part 1): You are working at a busy nightclub and have been monitoring a patron for the last hour. The patron has not ordered a single drink, but you have noticed significant changes in their behavior since they first arrived at the venue. They have become increasingly agitated, they have red bloodshot eyes, and they are very jittery, bouncing around, and talking at a rapid pace. Another employee has mentioned that they have seen the patron enter the toilets several times since they arrived at the venue. You start to think they could be affected by something other than alcohol, considering they have not ordered an alcoholic drink since they arrived. Consider what may cause this type of behavior.