# Etilamfetamine

Etilamfetamine, also known as N-ethylamphetamine and formerly sold under the brand names Apetinil and Adiparthrol, is a stimulant drug of the amphetamine family. It was invented in the early 20th century and was subsequently used as an anorectic or appetite suppressant in the 1950s, but was not as commonly used as other amphetamines such as amphetamine, methamphetamine, and benzphetamine, and was largely discontinued once newer drugs such as phenmetrazine were introduced.

## Pharmacology
### Pharmacodynamics
#### Monoamine releasing agent

Ethylamphetamine is a potent dopamine releasing agent (DRA) in vitro, with an EC$_{50}$Tooltip half-maximal effective concentration of 88.5 nM. This is about 10-fold lower than the EC$_{50}$ of dextroamphetamine. The EC$_{50}$ values of ethylamphetamine for induction of norepinephrine and serotonin release were not reported. However, the EC$_{50}$ values of its dextrorotatory enantiomer dextroethylamphetamine have been reported and were 44.1 nM, 28.8 nM, and 333 nM for norepinephrine, dopamine, and serotonin, respectively. Hence, dextroethylamphetamine acts as a norepinephrine–dopamine releasing agent (NDRA) with weak effects on serotonin.
In terms of structure–activity relationships, the potency of amphetamines as dopamine releasing agents and reuptake inhibitors decreases with increasing N-alkyl chain length. That is, the order of potency of N-alkylated amphetamines is as follows: amphetamine > methamphetamine > ethylamphetamine > propylamphetamine > butylamphetamine. Propylamphetamine is a weak dopamine reuptake inhibitor rather than releaser, whereas butylamphetamine is completely inactive as a dopamine releaser or reuptake inhibitor. The same relationship, for monoamine release and reuptake inhibition generally, has been shown with 4-methylamphetamine and its N-alkylated derivatives like 4-methylmethamphetamine and so forth.
Monoamine release of ethylamphetamine and related agents (EC$_{50}$Tooltip Half maximal effective concentration, nM) :
| Compound | NETooltip Norepinephrine | DATooltip Dopamine | 5-HTTooltip Serotonin |
| Phenethylamine | 10.9 | 39.5 | >10,000 |
| d-Amphetamine | 6.6–10.2 | 5.8–24.8 | 698–1,765 |
| d-Methamphetamine | 12.3–14.3 | 8.5–40.4 | 736–1,292 |
| Ethylamphetamine | ND | 88.5 | ND |
| d-Ethylamphetamine | 28.8 | 44.1 | 333.0 |
| Propylamphetamine | ND | RI (1,013) | ND |
| Butylamphetamine | ND | IA (>10,000) | ND |
| Notes: The smaller the value, the more strongly the drug releases the neurotransmitter. The assays were done in rat brain synaptosomes and human potencies may be different. See also Monoamine releasing agent § Activity profiles for a larger table with more compounds. Refs: |||||

#### Other actions

Ethylamphetamine is inactive as an agonist of the mouse and human trace amine-associated receptor 1 (TAAR1), whereas findings in the case of the rat TAAR1 are conflicting. In one study, its K$_i$ was 2,500 nM and its EC$_{50}$Tooltip half-maximal effective concentration (E$_{max}$Tooltip maximal efficacy) was 880 nM (62%) at the rat TAAR1 (i.e., it was a partial agonist), whereas its K$_i$ and/or EC$_{50}$ values at the mouse and human TAAR1 were >10,000 nM. In another study however, ethylamphetamine showed very little capacity to activate the rat TAAR1.

### Pharmacokinetics

Ethylamphetamine can be N-dealkylated into amphetamine (5–18% excreted in urine after 24 hours). As such, amphetamine may contribute to its effects in vivo.

## Chemistry

The molecular structure of ethylamphetamine is analogous to methamphetamine, with an ethyl group in place of the methyl group. It can also be considered a substituted amphetamine, with an ethyl group on the amphetamine backbone.
Analogues of ethylamphetamine include amphetamine, methamphetamine, propylamphetamine, isopropylamphetamine, butylamphetamine, fenfluramine (3-trifluoromethyl-N-ethylamphetamine), dimethylamphetamine, and 3-fluoroethamphetamine (3-fluoro-N-ethylamphetamine), among others.

## Society and culture
### Recreational use

Ethylamphetamine can be used as a recreational drug and, while its prevalence is less than amphetamine's, it is still encountered as a substance taken for recreational purposes. Ethylamphetamine produces effects similar to amphetamine and methamphetamine, though it is of lower potency.