Synthetic cathinones have recently emerged and grown to be popular drugs of abuse. Their dramatic increase has resulted in part from sensationalized media attention as well as widespread availability on the Internet. They are often considered "legal highs" and sold as "bath salts" or "plant food" and labeled "not for human consumption" to circumvent drug abuse legislation. Cathinone is a naturally occurring beta-ketone amphetamine analogue found in the leaves of the Catha edulis plant. Synthetic cathinones are derivatives of this compound. Those that are being used as drugs of abuse include butylone, dimethylcathinone, ethcathinone, ethylone, 3- and 4-fluoromethcathinone, mephedrone, methedrone, methylenedioxypyrovalerone (MDPV), methylone, and pyrovalerone. Synthetic cathinones are phenylalkylamines derivatives, and are often termed "bk-amphetamines" for the beta-ketone moiety. They may possess both amphetamine-like properties and the ability to modulate serotonin, causing distinct psychoactive effects. Desired effects reported by users of synthetic cathinones include increased energy, empathy, openness, and increased libido. Cardiac, psychiatric, and neurological signs and symptoms are the most common adverse effects reported in synthetic cathinone users who require medical care. Deaths associated with use of these compounds have been reported. Exposure to and use of synthetic cathinones are becoming increasingly popular despite a lack of scientific research and understanding of the potential harms of these substances. The clinical similarities to amphetamines and MDMA specifically are predictable based on the chemical structure of this class of agents. More work is necessary to understand the mechanisms of action, toxicokinetics, toxicodynamics, metabolism, clinical and psychological effects as well as the potential for addiction and withdrawal of these agents.