[Mephedrone, the new designer drug of abuse: pharmacokinetics, pharmacodynamics and clinical and forensic issues].

Mephedrone is a semisynthetic derivative of cathinone used as a drug of abuse. Similar to amphetamine, both in chemical structure and associated signs and symptoms, has gained popularity since 2007 and it is currently the sixth most abused drug in United Kingdom. It can be easily purchased by the internet or smart shops where it is advertised as a fertilizer for plants or bath salts, although such efficacy was never proved. This article aims to review the state-of-the-art literature of mephedrone, particularly its chemical structure, forms of presentation, pharmacokinetics, pharmacodynamics, acute intoxications, diagnosis and therapy of intoxications. Mephedrone is mainly sought for the following symptoms: euphoria, social disinhibition, empathy, and increased libido. However, its use is associated with several adverse effects on cardiovascular, gastrointestinal, neurological, psychiatric and genitourinary systems, among others. There are also reported cases of consumers who have developed tolerance and dependence after a regular abuse of mephedrone. Several deaths in the United Kingdom have been confirmed as being directly related to the consumption of mephedrone. Currently this drug is legally controlled in many countries, but little is known about its pharmacokinetics and pharmacodynamics. Most data comes only from users and health professional's reports and internet surveys. Recently, the Portuguese Law 13/2012, 26 of March, included mephedrone in the list of controlled substances, and therefore it is important to better understand this xenobiotic.