Piracetam (sold under many brand names) is a nootropic drug in the racetams group, with chemical name 2-oxo-1-pyrrolidine acetamide. It shares the same 2-oxo-pyrrolidone base structure with pyroglutamic acid. Piracetam is a cyclic derivative of the neurotransmitter gamma-aminobutyric acid (GABA), originally marketed in 1971 by UCB Pharma. Presently piracetam is used in many European countries, Asia and South America. In the United States, it is not approved by the US Food and Drug Administration for any medical use and it is not permitted to be sold as a dietary supplement. In the UK, piracetam is prescribed mainly for myoclonus but is used off-label for other conditions. Evidence to support its use for many conditions is unclear. Piracetam's mechanism of action, as with racetams in general, is not fully understood. The drug influences neuronal and vascular functions and influences cognitive function without acting as a sedative or stimulant. It is hypothesized to act on ion channels or ion carriers, thus leading to increased neuron excitability. GABA brain metabolism and GABA receptors are not affected by piracetam. It has been found to increase blood flow and oxygen consumption in parts of the brain, but this may be a side effect of increased brain activity rather than a primary effector mechanism of action for the drug.

Nizofenone (Ekonal, Midafenone) is a neuroprotective drug which protects neurons from death following cerebral anoxia (interruption of oxygen supply to the brain). It might thus be useful in the treatment of acute neurological conditions such as stroke. Nizofenone ameliorates various pathophysiologic events during ischemia, such as ATP depletion, lactate accumulation, glutamate release, free fatty acid liberation, edema, and neuronal degeneration; in particular, ischemia-induced excessive glutamate release has been completely blocked by this drug. This drug has also radical-scavenging action, comparable to vitamin E, and inhibits oxygen radical-induced lipid peroxidation. The potent cerebroprotective effect of nizofenone has been demonstrated in various experimental models of cerebral hypoxia, ischemia (focal and global), ischemia-reperfusion, and infarction. The clinical efficacy of nizofenone has been proved by pioneering double-blind studies in acute subarachnoid hemorrhage patients. Nizofenone is clinically used for preventing the delayed ischemic neurologic deficits due to late vasospasm following subarachnoid hemorrhage.

Orazamide, which is composed of one molecule of 5-aminoimidazole-4-carboxamide (AICA), one molecule of orotic acid and two molecules of water, is used clinically for the treatment of hepatitis and cirrhosis The nucleoside of AICA (AICAR) is internalized and becomes phosphorylated by adenosine kinase to form AICAR mono-phosphate (AICA ribotide, ZMP), an intermediate in the late steps of de novo purine biosynthesis. In hepatocytes, AICA can inhibit the fatty acid synthesis, sterol synthesis, and gluconeogenesis.

Xaliproden is an orally active 5HT1-A receptor antagonist that was being developed by Sanofi. It has been evaluated for the treatment of Alzheimer's disease and amyotrophic lateral sclerosis (ALS), and protection against peripheral neurotoxicity associated with certain cancer chemotherapies. Two large, 18-month, clinical trials of xaliproden (monotherapy or adjunctive therapy, respectively) in patients with mild to moderate AD (MMSE, 16–26, inclusive) were completed in 2007. Failure to demonstrate sufficient efficacy in both trials resulted in cancelation of the xaliproden development program for AD in September 2007.

Lobenzarit is an immunomodulator and antioxidative agent, which has been used successfully in Japan for the treatment of rheumatoid arthritis. Lobenzarit is a scavenger of oxygen-free radicals such as hydroxyl radicals, superoxide, peroxyl and singlet oxygen. Side effects of this medicine are: decreased/considerably increased urinary volume, bloody urine, frequent urination.

Bergenin, isolated from Bergenia ligulata is a potent antioxidant and antilithiatic agent. Bergenin is an effective and broad-spectrum antifungal and antiviral Chinese medicine. Bergenin was reported to possess anti-microbial properties against filamentous fungi, yeast and HIV, but not against bacteria. Bergenin also exhibits anti-inflammatory activity through the inhibition of cyclo-oxygenase-2 or by means of affecting the Th1- or Th2-skewed cytokine production. Bergenin also exerts an anti-oxidant effect by scavenging free radicals, such as H, OH and CH3. In addition, bergenin was reported to possess hepatoprotective, neuroprotective and gastroprotective properties. R. aesculifolia Batal containing bergenin was used to treat protozoal infection and fever in rural China. Also was evaluated the antimalarial activity of bergenin in vitro and in vivo trials. Bergenin effectively inhibited Plasmodium falciparum growth in vitro (IC50, 14.1 µg̸ml, with ~100% inhibition at 50 µg/ml), without apparent cytotoxicity to erythrocytes or to mammalian HeLa and HepG2 cells. Bergenin exhibited less cytotoxic activity and the selectivity index (SI) was 887 and 1,355 for HeLa and HepG2 cells, respectively. The administration of bergenin to Plasmodium berghei infected mice for 6 days significantly inhibited the growth of the parasites. These findings provide evidence that bergenin may be a promising novel drug for antimalarial treatment. Antioxidant potential of bergenin was shown based on decreasing in lipid peroxides and increasing in superoxide dismutase (SOD) and catalase (CAT). Histopathological studies demonstrated the regenerative effect of bergenin on pancreatic β cells. Was shown, that bergenin isolated from C. digyna possesses significant antidiabetic, hypolipidemic and antioxidant activity in Type 2 diabetic rats.

Aptiganel (CNS 1102, Cerestat), a selective ligand with antagonized properties for the ion-channel site of the N-methyl-D-aspartate receptor-channel complex, was developed as a neuroprotective agent for focal brain ischemia. However, in the clinical trials in patients with acute ischemic stroke aptiganel was not efficacious at either of the tested doses and may be harmful. That is why its further study was discontinued.

Meldonium (3-(2,2,2-trimethylhydrazinium)propionate; MET-88; quaterine, trade-named as Mildronate) is an antiischemic drug developed at the Latvian Institute of Organic Synthesis. It is a clinically used in the treatment of heart failure, myocardial infarction, arrhythmia, atherosclerosis, and diabetes. Mechanism of action is based on the regulation of energy metabolism pathways through l-carnitine lowering effect. L-Carnitine biosynthesis enzyme γ-butyrobetaine hydroxylase and carnitine/organic cation transporter type 2 (OCTN2) are the main known drug targets of meldonium, and through inhibition of these activities, meldonium induces adaptive changes in the cellular energy homeostasis. Since L-carnitine is involved in the metabolism of fatty acids, the decline in its levels stimulates glucose metabolism and decreases concentrations of l-carnitine related metabolites, such as long-chain acylcarnitines and trimethylamine-N-oxide. Meldonium is used in neurological clinics for the treatment of brain circulation disorders. It appears to improve patients' mood; they become more active, their motor dysfunction decreases, and asthenia, dizziness, and nausea become less pronounced. CNS effects of Meldonium could be mediated by stimulation of the nitric oxide production in the vascular endothelium by modification of the gamma-butyrobetaine and its esters pools. It is hypothesized that mildronate may increase the formation of the gamma-butyrobetaine esters. Meldonium was on the World Anti-Doping Agency’s (WADA) list of drugs being monitored until September 2015, when it was added to the list of banned substances, effective January 1, 2016.

Tisopurine (or Thiopurinol) was used in the treatment of gout. This drug reduces uric acid concentrations by interfering with the early stages of its synthesis, thus avoiding increased blood concentrations of hypoxanthine and xanthine. In addition, it was discovered, that tisopurine caused acute hepatitis.

Hopantenic acid (homopantothenic acid) is a central nervous system depressant. Formulated as the calcium salt, it is used as a pharmaceutical drug in the Russian Federation under the brand name Pantogam. In Russia it is widely used to treat a variety of neurological, psychological and psychiatric conditions. The drug has been on the pharmaceutical market since 1979 and has been proven to be safe even for children from 3 years old upwards. Hopantenic acid is a natural forming substance, has some of the lowest side effects and considered to be very safe. Use Pantogam to treat a wide variety of cognitive and nervous system disorders with combined sedative and mild stimulant effect. Hopantenic acid is not approved for use in Europe or the United States. GABA receptor agonist.