N-Ethylpentylone (ò-keto-ethylbenzodioxolylpentanamine, òk-ethyl-K, òk-EBDP, ephylone) is a substituted cathinone and stimulant drug which was developed in the 1960s.
It has been reported as a novel designer drug in several countries including the United Kingdom, South Africa, New Zealand, the United States, and Australia. In 2018, N-ethylpentylone was the most common drug of the cathinone class to be identified in Drug Enforcement Administration seizures.
N-Ethylpentylone has been reported to cause lethal heart palpitations and hallucinations. It has been linked to a number of overdose deaths and hospitalisations, and has increasingly been mis-sold as MDMA.
N-Ethylpentylone is primarily a mixed norepinephrine reuptake inhibitor and dopamine reuptake inhibitor. It binds to transporters with IC<sub>50</sub> values of 37 nM (dopamine transporter), 105 nM (norepinephrine transporter) and 383 nM (serotonin transporter). The methylenedioxy ring-substitution provides a higher potency at inhibiting serotonin reuptake than its analogue N-ethylpentedrone. N-Ethylpentylone is also a low-potency serotonin 5-HT<sub>2A</sub> receptor agonist, with an of 5,200nM.
In vivo studies in mice demonstrated that acute intraperitoneal administration of N-ethylpentylone induced an increase in locomotor activity, anxiolytic effects but also an aggressive behaviour as well as social exploration deficits. Repeated exposure to N-ethylpentylone induced hyperthermia, anorexia and rewarding effects. During withdrawal after repeated administration, depression-like symptoms, hyperlocomotion, and a decrease of social exploration were observed.