Synthetic stimulants marketed as "bath salts" contain chemicals like mephedrone and MDPV that are derived from cathinone, a stimulant found in khat plants. These chemicals are sold in powder or tablet form under various brand names and can be snorted, swallowed, smoked, or injected. They cause effects like agitation, paranoia, and increased heart rate. While some countries have banned them, they have no approved medical use in the US and incidents involving them can be prosecuted under the Controlled Substances Act due to their similarity to illegal drugs.