These drugs generally fall into one of two categories: the synthetic cannabinoids or the synthetic cathinones.

Synthetics cannabinoids are human-made mind-altering chemicals that are either sprayed on dried, shredded plant material so they can be smoked or sold as liquids to be vaporized and inhaled in e-cigarettes and other devices.

Synthetic cathinones are better known as bath salts. Unlike bath salts that look like large crystals that are placed in bathtubs, these bath salts are fine powders that are inhaled, insufflated, or injected and act like amphetamines. 

Their popularity stems from the fact that many if not all do not show up on standard drug screens, and because of how easy it is to buy them. One of the dangers, however, is that the user never truly knows what they are purchasing and many packets actually contain combinations of different synthetic drugs.

Synthetic drugs are incredibly potent and have severe health effects. Intoxicated patients can present with sympathomimetic toxicity. In addition, there are multiple reports of stroke, seizure, heart attacks, intracranial hemorrhage, paranoia, and suicidal ideation associated with these agents.

Even for patients that do not suffer long-term consequences, they can take hours to sober before they are safe for discharge from the emergency department.