Spaglumic acid (NAAG) is the β-aspartyl isoform of N-Acetyl-l-aspartylglutamate (isospaglumic Acid is N-(N-Acetyl-l-α-aspartyl)-l-glutamic acid). In eye drops, spaglumic acid is either a magnesium or sodium salt of N-Acetyl-l-aspartylglutamate. Spaglumic acid is a mast cell stabilizer. Thus it is used in allergic conditions such as allergic conjunctivitis. Specifically spaglumic acid is approved in Portugal under the brand name Naabak and in Greece under the brand name Naaxia for use in patients with allergic conjunctivitis. Spaglumic Acid is a peptide neurotransmitter and the third-most-prevalent neurotransmitter in the mammalian nervous system. It is a weak activator of NMDA receptors and a highly selective agonist for mGlu3 receptors. Spaglumic Acid is neuroprotective under non-hydrolysing conditions in vivo.

Phenibut (beta-phenyl-gamma-aminobutyric acid or 4-amino-3-phenylbutyric acid) is a neuropsychotropic drug that was discovered and introduced into clinical practice in Russia in the 1960s. It has anxiolytic and nootropic (cognition enhancing) effects. It acts as a GABA-mimetic, primarily at GABA(B) receptors. Pharmacological activity of racemic phenibut relies on R-phenibut and this correlates to the binding affinity of enantiomers of phenibut to the GABAB receptor. In addition R-phenibut binds to the α2-δ subunit of voltage-dependent calcium channels. It is highly effective in treating anxiety, post-traumatic stress disorder, depression, asthenia, insomnia, alcoholism, stuttering, and vestibular disorders. It also improves mental performance (attention, memory, speed and accuracy of sensory-motor reactions), physical performance, reduces sleep disorders as well as movement and speech disorders.

Phenibut (beta-phenyl-gamma-aminobutyric acid or 4-amino-3-phenylbutyric acid) is a neuropsychotropic drug that was discovered and introduced into clinical practice in Russia in the 1960s. It has anxiolytic and nootropic (cognition enhancing) effects. It acts as a GABA-mimetic, primarily at GABA(B) receptors. Pharmacological activity of racemic phenibut relies on R-phenibut and this correlates to the binding affinity of enantiomers of phenibut to the GABAB receptor. In addition R-phenibut binds to the α2-δ subunit of voltage-dependent calcium channels. It is highly effective in treating anxiety, post-traumatic stress disorder, depression, asthenia, insomnia, alcoholism, stuttering, and vestibular disorders. It also improves mental performance (attention, memory, speed and accuracy of sensory-motor reactions), physical performance, reduces sleep disorders as well as movement and speech disorders.

DAU 6215 (Itasetron) is a selective 5-hydroxytryptamine3 (5-HT3) antagonist, which was developed by Boehringer Ingelheim. And was investigated for treatment the nausea and vomiting induced by chemotherapy, it was confirmed that this drug possessed antiemetic properties. Also was discovered, that chronic treatment with itasetron significantly improved retention abilities of the aged rats in this memory test. However, development of itasetron was terminated.

Heptaminol is an amino alcohol that has been used as a myocardial stimulant and vasodilator and to relieve bronchospasm. Its most common therapeutic use is in orthostatic hypotension. The mechanism of heptaminol's therapeutic actions is not well understood although it has been suggested to affect catecholamine release or calcium metabolism.

Meptazinol is a unique opioid analgesic. Binding studies suggest a relative selectivity for mu-1 opioid receptor sites. Meptid is indicated for the treatment of moderate to severe pain, including post-operative pain, obstetric pain and the pain of renal colic. The most commonly reported adverse reactions after treatment with meptazinol are nausea, vomiting, dizziness, diarrhoea and increased sweating, constipation, abdominal pain, rash, vertigo, headache, drowsiness, somnolence and dyspepsia.

Pipethanate ethobromide is an antimuscarinic with actions similar to those of atropine. It has been used in the symptomatic treatment of visceral spasms in oral doses of up to 160 mg daily in divided doses. Pipethanate ethobromide has also been given intramuscularly or intravenously in doses of 10 to 20 mg daily and rectally in doses of 60 or 120 mg daily.

Nicergoline is a semisynthetic ergoline derivative that has been used as a cerebral vasodilator and in peripheral vascular disease. Nicergoline seems to have an action: (i) as an alpha1-adrenoceptor antagonist, it induces vasodilation and increases arterial blood flow; (ii) it enhances cholinergic and catecholaminergic neurotransmitter function; (iii) it inhibits platelet aggregation; (iv) it promotes metabolic activity, resulting in increased utilization of oxygen and glucose; and (v) it has neurotrophic and antioxidant properties. Nicergoline has been suggested to ameliorate cognitive deficits in cerebrovascular disease.

Zanapezil (TAK-147) is a selective reversible acetylcholine (ACh) esterase inhibitor that was designed as a drug for Alzheimer's disease (AD) treatment. The development of the drug was discontinued due to a lack of a dose-dependent effect in the trials.

Taltirelin (TA-0910), a synthetic thyrotropin-releasing hormone (TRH) analog, has been developed by Tanabe Seiyaku for the treatment of neurodegenerative diseases. Taltirelin mimics the physiological actions of TRH, but with a much longer half-life and duration of effects, and little development of tolerance following prolonged dosing. Taltirelin has nootropic, neuroprotective and analgesic effects. Taltirelin is primarily being researched for the treatment of spinocerebellar ataxia; limited research has also been carried out with regard to other neurodegenerative disorders, e.g., spinal muscular atrophy.