Initially, 4-FA was used as an adulterant, but it became a drug of choice over the last decade. Its prevalence of use among Dutch party-goers (15–35 years) increased rapidly from 9% in 2013 to 25% in 2016 and it showed a global presence on the drug market.

Although 4-FA is an illicit drug in the Netherlands since 2017, 4-FA continued to be the most prominent novel psychoactive substance in the Netherlands in 2018, with 0.9% of all Dutch adults having used 4-FA in that year, compared to 2.8% MDMA and 1.1% amphetamine use.

Importance of Buy 4-FA

The popularity of 4-FA might be due to the described effect as intermediate between MDMA and amphetamine. In case reports and small case studies, serious complications, such as heart failure, cardiomyopathy, myocardial infarction, cerebral hemorrhage, seizures, hyperpyrexia, and fatalities, have been described, which are comparable to previously described MDMA- and amphetamine-related complications.

Due to these similarities, emergency department (ED) management of 4-FA intoxications is mostly similar to MDMA and amphetamine, although specific management may be indicated based on specific clinical effects of 4-FA.

Patient selection

Patients ≥18 years old with self-reported and/or toxicology analysis confirmed 4-FA, amphetamine, and MDMA intoxication, presenting between November 2015 and March 2020, were identified from the OLVG toxicology registration and included for retrospective analysis. OLVG patients are prospectively included in a toxicology registry when they present to the ED with an intoxication-related complaint.

Acceptable synonyms for these drugs were 4-FMP, XTC, ecstasy, speed, and pep. Patients were identified and selected for a specific study group via self-reported drug use (SRDU), and when available confirmed with a urine toxicology screening (UTS) or high-resolution mass spectrometry.

Toxicological analysis results were unavailable for most patients because serum analysis was not routinely performed. UTS was performed using a point-of-care immunoassay test (Triage TOX Drug Screen, Alere Inc.) able to detect methamphetamine/MDMA, amphetamine, cocaine, methadone, tetrahydrocannabinol (THC), and benzodiazepine. UTS results were considered superior to SRDU, with the exception of benzodiazepines because they could have been administered by healthcare personnel and 4-FA because 4-FA is not detected by UTS. In a previous study, no false–positive results were found for amphetamine or methamphetamine with the Triage TOX Drug Screen. A false–positive SRDU was deemed unlikely.

Patients with amphetamine type stimulant use other than 4-FA, MDMA, and/or amphetamine and non–intoxication-related primary ED presenting complaints were excluded.

Included patients were divided into 3 study groups depending on the type of drug used, namely mono-drug intoxication (only 1 substance used), multi-drug intoxication (more than 1 substance used, but only 1 of the study substances 4-FA, MDMA, and/or amphetamine), or cross-drug intoxication (a combination of 4-FA, MDMA, and/or amphetamine, with or without other substances used).

To determine mono- or multi-drug intoxication, SRDU, UTS results, and alcohol serum levels were used. A serum ethanol level above 0.1 g/L was considered an alcohol intoxication and, consequently, multi-drug intoxication.