Prochlorperazine is a piperazine phenothiazine antipsychotic which block postsynaptic mesolimbic dopaminergic receptors in the brain and has antiemetic effects by its antagonist actions in the D2 dopamine receptors in the chemoreceptor trigger zone. It also exhibits alpha-adrenergic blocking effect on α1 receptros and may depress the release of hypothalamic and hypophyseal hormones. Prochlorperazine is used for the control of severe nausea and vomiting, for the treatment of schizophrenia. Prochlorperazine is effective for the short-term treatment of generalized non-psychotic anxiety. Prochlorperazine may be an effective treatment of acute headaches and refractory chronic daily headache.

Chlorpromazine is a psychotropic agent indicated for the treatment of schizophrenia. It also exerts sedative and antiemetic activity. Chlorpromazine has actions at all levels of the central nervous system-primarily at subcortical levels-as well as on multiple organ systems. Chlorpromazine has strong antiadrenergic and weaker peripheral anticholinergic activity; ganglionic blocking action is relatively slight. It also possesses slight antihistaminic and antiserotonin activity. Chlorpromazine acts as an antagonist (blocking agent) on different postsysnaptic receptors -on dopaminergic-receptors (subtypes D1, D2, D3 and D4 - different antipsychotic properties on productive and unproductive symptoms), on serotonergic-receptors (5-HT1 and 5-HT2, with anxiolytic, antidepressive and antiaggressive properties as well as an attenuation of extrapypramidal side-effects, but also leading to weight gain, fall in blood pressure, sedation and ejaculation difficulties), on histaminergic-receptors (H1-receptors, sedation, antiemesis, vertigo, fall in blood pressure and weight gain), alpha1/alpha2-receptors (antisympathomimetic properties, lowering of blood pressure, reflex tachycardia, vertigo, sedation, hypersalivation and incontinence as well as sexual dysfunction, but may also attenuate pseudoparkinsonism - controversial) and finally on muscarinic (cholinergic) M1/M2-receptors (causing anticholinergic symptoms like dry mouth, blurred vision, obstipation, difficulty/inability to urinate, sinus tachycardia, ECG-changes and loss of memory, but the anticholinergic action may attenuate extrapyramidal side-effects). Additionally, Chlorpromazine is a weak presynaptic inhibitor of Dopamine reuptake, which may lead to (mild) antidepressive and antiparkinsonian effects. Chlorpromazine has being marketed under the trade names Thorazine and Largactil among others. Chlorpromazine is used for treating certain mental or mood disorders (eg, schizophrenia), the manic phase of manic-depressive disorder, anxiety and restlessness before surgery, the blood disease porphyria, severe behavioral and conduct disorders in children, nausea and vomiting, and severe hiccups.

Glycine (Cly) is a natural amino acid neurotransmitter that acts as a co-agonist at Glutamate [NMDA] receptors in the brain and is an activator of glycine receptors, GLRA1-3, GLRB. The abnormal Gly levels have been implicated in neuropsychiatric disorders. Alterations in Gly levels are implicated in several diseases of the central nervous system. Glycine was studied in phase II of clinical trials in patients with schizophrenia. The results have shown that using of glycine was associated with reduced symptoms with promising effect sizes and a possibility of improvement in cognitive function. Besides, glycine was also studied in clinical trials phase II in children with cystic fibrosis. The clinical, spirometric and inflammatory status of subjects with cystic fibrosis improved after just 8 weeks of glycine intake, suggesting that this amino acid might constitute a novel therapeutic tool for these patients. In addition, Gly was proposed as a biomarker for brain tumor malignancy. Glycine is a component of a nutrients mixture for peripheral administration to well-nourished mildly catabolic adult patients who require only short-term parenteral nutrition.

Neboglamine is a functional modulator of the glycine site on the N-methyl-D-aspartate (NMDA) receptor. Neboglamine appeared to promote neuronal growth as measured by expression of Fos-like immunoreactivity, particularly in the prefrontal cortex, nucleus accumbens, and lateral septal nucleus. Neboglamine behaves as a potential antipsychotic. Neboglamine is in phase II clinical trials by Rottapharm for the treatment of schizophrenia and cocaine abuse.

Dicarbine is an orally active drug approved in Russia under the trade name Карбидин, is used for the treatment patients with schizophrenia and alcoholic psychosis. This drug blocks dopamine receptors in various brain parts, which leads to a reduction in the productive symptoms of psychosis: delusions and hallucinations.

Tiospirone (TSP) is an atypical antipsychotic drug. Tiaspirone appeared to be a promising antipsychotic agent as it didn`t cause extrapyramidal syndromes. It has 5HT-2 antagonistic properties as well as affinity for D2, 5HT-1a, 5HT-6 and sigma receptors. Tiospirone was in phase III clinical trials for the treatment of attention hyperactivity disorder with Mead Johnson in the USA but its development appears to have been discontinued.

Xanomeline (LY-246,708) is an orthosteric muscarinic acetylcholine receptor (mAChR) agonist, often referred to as M1/M4-preferring. It is also known to act as a M5 receptor antagonist. Xanomeline was studied in clinical trials phase I in schizophrenia. In Phase II clinical trials in Alzheimer’s patients, xanomeline significantly improved several measures of cognitive function, yet produced unwanted side effects that limited patient compliance. The side effects seem to be associated with rapid metabolism of the alkyloxy side chain following oral administration, resulting in a nonselective, yet active compound with limited therapeutic utility. Despite a second Phase II clinical trial with a patch formulation, the liabilities of xanomeline still outweigh its benefits.

(-)-3-(3-hydroxyphenyl)-N-n-propylpiperidine ((-)-3-PPP, also known as preclamol) has a dual action towards to dopamine D2 autoreceptor: it activates it and also acts concomitantly as an antagonist at postsynaptic DA receptors. It was shown, that (-)-3PPP/preclamol was a safe drug for study in the treatment of schizophrenia and may have antipsychotic efficacy. Besides, the motor effects of the drug were evaluated in nine patients with Parkinson's disease using a double-blind, placebo-controlled design. However, the small number of patients manifesting a clinically significant response and the frequently inconsistent effects could indicate that this class of agents may have relatively limited clinical utility.

Eliprodil, also known as SL 82-0715, is a non-competitive NMDA glutamate receptor antagonist, which targets the polyamine modulatory site and is selective for NR2B subunit-containing receptors. Eliprodil was in phase III clinical trial for the treatment of stroke or traumatic brain injury. However, these investigations were failed. One reason suggested for failure was that eliprodil had blocked the synaptic transmission mediated by NMDA receptors, hindering neuronal survival. In addition, eliprodil has been studied in phase II clinical trials for the treatment of Parkinson's disease.

Talaglumetad (also known as LY-544344) is a bicyclohexane derivative patented by Eli Lilly and Company as modulators of metabotropic glutamate receptor. Talaglumetad acts as a prodrug of Eglumegad, a selective agonist of metabotropic glutamate receptors (mGluR2/3) and metabolized to release active compound by both human jejunal homogenates and rat liver homogenates. In experiments on mice, Talaglumetad was found to be as effective as diazepam for treating anxiety symptoms in several standard tests, but without producing any of the negative side effects of diazepam such as sedation and memory impairment.