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.

Alpha methyltryptamine (AMT) is a tryptamine (indole ethylamine) derivative, which was developed in the 1960's by Upjohn with the intention for use as an antidepressant. It was used in Russia under the trade name Indopan for the treatment of Bipolar disorder and some form of depression, but currently not being produced because of serious side effects. In the 1990's, alpha-methyltryptamine became regulated as a Schedule I controlled substance in the United States. Pharmacologically, AMT has high affinity for the serotonin (5-HT) transporter, a number of 5-HT receptors, and potently inhibits reuptake of monoamines dopamine, 5-HT, and norepinephrine reuptake. AMT is also a monoamine oxidase A inhibitor that conceivably could contribute to its pharmacological effect and this drug also the most potent inhibitor of semicarbazide-sensitive amine oxidase (SSAO).

O-Desmethyl tramadol (O-Desmethyltramadol, O-DSMT) is a metabolite of tramadol. O-Desmethyltramadol is an opioid analgesic and the main active metabolite of tramadol. (+)-O-Desmethyltramadol is the most important metabolite of tramadol produced in the liver after tramadol is consumed. This metabolite is considerably more potent as a μ-opioid agonist than the parent compound. O-desmethyl tramadol, inhibits 5-hydroxytryptamine type 2C receptors expressed in xenopus oocytes. O-desmethyl tramadol inhibits functions of M(1) receptors but has little effect on those of M(3) receptors. O-desmethyl tramadol has been widely used clinically and has analgesic activity.