Etonitazene is a potent and selective mu-opioid agonist. It was developed in CIBA. Administration of etonitazene may induce respiratory depression, and therefor etonitazene is not used in humans. Etonitazene is explicitly listed as an illegal drug under UN convention and is illegal throughout the world.

ORG-28611 (SCH-900,111) is a potent cannabinoid receptor full agonist, developed by Organon International for treatment pain. In preclinical studies, Org 28611 exhibited high affinity for both CB1 and CB2 cannabinoid receptors, as determined by radioligand competition binding assays and rapidly metabolized by mouse and human hepatic microsomes and showed higher total levels in the brain compared to plasma. In clinical trials, Org 28611 does not provide enough sedation for outpatient surgical procedures, does not induce anterograde amnesia and causes undesirable subjective effects at higher doses. However, bolus doses up to 3 μ/kg (with maximum initial plasma concentrations of 24 ng/mL) or mean plasma levels up to 4 ng/mL are well tolerated and make it worthwhile to further explore the analgesic or antiemetic properties.

Desmethylmoramide is a morpholinopyrrolidine. Being opioid receptor agonist it might be used as narcotic analgesic.

Brolamfetamine (also known as DOB, bromo-DMA, and 4-bromo-2,5-dimethoxyphenylisopropylamine) is one of a vast number of compounds used recreationally to achieve hallucinogenic effects. Brolamfetamine is one of the most potent hallucinogens, with its hallucinogenic potency directly linked to its abuse potential. Brolamfetamine acts as a partial agonist of 5HT2A, 5HT2B, 5HT2C, and TAAR1 receptors, but it’s psychedelic effects are mainly mediated by its agonistic properties at the 5-HT2A receptor. Animal studies have shown physiologic effects including hypertension, tachycardia, hyperpyrexia, pupillary dilatation, and peripheral vasoconstriction. In general, Brolamfetamine having a similar effect to LSD, with slower onset (up to 3–4 h to peak intoxication) and longer duration of effect (up to 36 h). Brolamfetamine is not commonly available, through periods of higher circulation were reported in Australia in 1983, Ireland in 2003, and in Italy in 2015. Brolamphetamine, as well as many other synthetic hallucinogens, are increasingly being sold as LSD. Internationally Brolamfetamine is a Schedule I drug under the Convention on Psychotropic Substances. Due to its selectivity, Brolamfetamine is often used in scientific research when studying the 5-HT2 receptor subfamily.

Dizocilpine (MK-801) is an antagonist of the N-methyl-D-aspartate (NMDA) receptor in the glutamate category involved with the central nervous system (CNS). The drug displays a variety of physiological actions, many of which involve the CNS, such as anesthetic and anticonvulsant properties. It penetrates readily into CNS and was described as the agent with central sympathomimetic properties. Co-administration of dizocilpine with psychostimulants, such as cocaine, amphetamine and nicotine, has been reported to prevent the development of behavioural sensitization to these drugs as well as associated neuroadaptations in rodents. However, studies with bromocriptine have suggested that co-administration of dizocilpine might merely cause sensitization to become state-dependent. A single injection of MK-801 to rats models both positive and negative symptoms of schizophrenia. Treatment of mice with dizocilpine induced learning impairment.

m-Chlorophenylpiperazine (meta-chlorophenylpiperazine or mCPP) is a psychoactive substance, which is illegal in many countries but can be found on the black market. It induces endocrine, neurological and psychiatric effects. mCPP is a partial agonist at the 5-HT2C receptor but antagonized the 5-HT2B and 5-HT3 receptors. mCPP is also an active metabolite of the drug trazodone, which is used as an effective antidepressant drug with a broad therapeutic spectrum, including anxiolytic efficacy. It is known, that mCPP induces migraine attacks and that the decrease of food intake induced by the mCPP depends on its ability to act as a serotonin agonist is a brain.

Amfonelic acid (AFA) is a dopamine reuptake inhibitor. Experiments on rats have shown that AFA treatment completely prevented the effects of methamphetamine on the dopaminergic system, both morphologically and biochemically.

N,N-Dimethyl-5-Methoxytryptamine (aka 5-MeO-DMT) is a psychedelic of the tryptamine class. It is found in a wide variety of plant species, and a single psychoactive toad species, the Colorado River toad. Like its close relatives DMT and bufotenin (5-HO-DMT), it has been used as an entheogen in South America. It can also be found in the dart poison traditionally used by the Yanoama Indians of Upper Orinoco. It acts as a non-selective serotonin (5-HT) agonist. -MeO-DMT is O-demethylated by polymorphic cytochrome P450 2D6 (CYP2D6) to an active metabolite, bufotenine. 5-MeO-DMT is classified as a controlled substance in China, Australia, Sweden, Turkey, and the USA.

Growth hormone releasing hexapeptide (GHRP-6) is a synthetic met-enkephalin analog that induces the release of growth hormone in vivo through binding of the ghrelin receptor. GHRP-6 increases proliferation in astrocytes through a mechanism that involves PI3K/Akt signaling. GHRP-6 also inhibits development of restraint stress-induced gastric lesions and reverses ovariectomy-induced effects on serum glucose and insulin levels. Additionally, GHRP-6 decreases locomotor activity and increases food intake in vivo. Essentially a synthetic version of ghrelin analogue, GHRP-6 (like GHRP-2) stimulates the release of an endogenous growth hormone (GH) within the somatotropes of the anterior pituitary in the animal and human body. Specifically, GHRP-6 will increase the number of somatotropes in a GH pulse by limiting the amount of somatostatin present, while standard GHRH increases the amplitude at which the pituitary cells pulse. Unlike ghrelin, GHRP-6 is not specifically used to increase appetite, but it may have secondary actions that impact hypothalamic neurons. These effects last for approximately an hour after the initial application, which mimics the natural application of GH, and consists of an eight hour circulation period. In studies GHRP-6 has shown biological actions similar to the naturally occurring hunger stimulating peptide ghrelin. Its main use is to promote food intake by stimulating hunger and aid in energy metabolism. It can be used in the treatment of GH deficiency as well as cachexia, eating disorders and obesity. GHRP-6 is a synthetic met-enkephalin (a naturally occurring opioid growth factor) analog. GHRP-6 contains D-amino acids that are entirely synthetic, lacks opioid activity, and shares no sequence relation with GHRH. It has also been shown that GHRP-6 can lead to re-stimulation of the natural production of HGH. Studies have shown that GHRP-6 increases the secretion of IGF-1 (InsulinLike Growth Factor 1) by the liver, which is speculated to be a required component in the anabolic mechanisms leading to the action of HGH. It also appears that GHRP-6 has positive implications for the central nervous system, as ghrelin is known to protect neurons.