Obviously, using only one substance at a time is much safer and less risky than being cross-faded from mixing multiple substances.
Mixing substances intensifies the high but also the impairment, which can lead to more accidents and riskier behavior. This can increase the chances of getting into an accident or being pulled over for a driving under the influence (DUI) arrest.
In addition, the unhealthy symptoms of nausea, vomiting, and anxiety are enhanced when an individual is cross-faded.