Nitrovin (hydrochloride salt) is a discontinued food additive that was used in veterinarian practice to promote growth. Nitrovin was shown to inhibit Salmonella growth both in vitro and in vivo (in chickens).

Zaldaride is a calmodulin antagonist known to produce inhibition of calmodulin-dependent voltage-gated ion channels including those of Ca2 , Na , and K . Zaldaride was also observed to inhibit nicotinic acetylcholine receptor (nAChR) channel currents. Zaldaride has been studied in clinical trials as a potential treatment for travelers diarrhea.

Silymarin, a plant-derived flavonoid from the plant Silybum marianum, is considered the most potential drug to treat almost all kind of liver diseases, particularly alcoholic liver disease, acute and chronic viral hepatitis and toxins-mediated liver dysfunctions. The main component of the silymarin complex is silybin, synonymous with silibinin, sometimes incorrectly called silybinin, which is a mixture of two diastereomers A and B in approximately 1:1 proportion. The drug possess hepatoprotective and antioxidant activity. The hepatoprotective effect is due to stimulation of synthesis of structural and functional proteins and phospholipids, as well as acceleration of the regeneration of hepatocytes. Antioxidant effect is determined by interaction of bioflavones with free radicals in the liver and its detoxication. In such manner the process of peroxidation of the lipids is interrupted and further liver destruction is prevented. Side effect is a mild laxative effect has occasionally been observed.

Rimonabant (also known as SR141716; trade names Acomplia, Zimulti) was an anorectic antiobesity drug that was first approved in Europe in 2006 but was withdrawn worldwide in 2008 due to serious psychiatric side effects. Rimonabant is an inverse agonist for the cannabinoid receptor CB1 and was the first drug approved in that class. There is considerable evidence that the endocannabinoid (endogenous cannabinoid) system plays a significant role in appetitive drive and associated behaviors. It is, therefore, reasonable to hypothesize that the attenuation of the activity of this system would have therapeutic benefit in treating disorders that might have a component of excess appetitive drive or over-activity of the endocannabinoid system, such as obesity, ethanol and other drug abuse, and a variety of central nervous system and other disorders. Data from clinical trials submitted to regulatory authorities showed that rimonabant caused depressive disorders or mood alterations in up to 10% of subjects and suicidal ideation in around 1%, and in Europe, it was contraindicated for people with any psychiatric disorder, including depressed or suicidal people. Additionally, nausea and upper respiratory tract infections were very common (occurring in more than 10% of people) adverse effects; common adverse effects (occurring in between 1% and 10% of people) included gastroenteritis, anxiety, irritability, insomnia and other sleep disorders, hot flushes, diarrhea, vomiting, dry or itchy skin, tendonitis, muscle cramps and spasms, fatigue, flu-like symptoms, and increased risk of falling.

Bucindolol is a third-generation, non-selective β-adrenergic receptor blocker, that acts on both β-1 and β-2 receptors. Bucindolol’s additional α-1 antagonistic activity contributes to its mild vasodilator effect. It was rejected by the FDA for the heart failure, because of the unreviewed submissions deal with comparative effectiveness, clinical pharmacology, some aspects of pharmacogenetic data, and toxicology/metabolism. In addition, bucindolol is in the phase II of clinical trial for the treatment of atrial fibrillation.

Thiocolchicoside is a muscle relaxant that has been authorised by national procedures in several EU Member States for use by mouth or injection into the muscles in the treatment of painful muscular disorders. Thiocolchicoside is marketed under the brand name Muscoril among others. Thiocolchicoside (TCC) is used clinically for its muscle relaxant, anti-inflammatory, and analgesic properties, and it has been shown to interact with gamma-aminobutyric acid (GABA) type A receptors (GABAARs) and strychnine-sensitive glycine receptors in the rat central nervous system.

Bopindolol (4-[benzoyloxy-3-tertbutylaminopropoxy]-2-methylindole hydrogen malonate) is an indole beta-adrenoceptor antagonist bearing a benzoyl ester residue on the beta-carbon atom of the propanolamine side chain. Bopindolol is metabolized by esterase to benzoic acid and an active metabolite, 18-502 [4-(3-t-butylamino-2-hydroxypropoxy)-2-methyl indole], which is further metabolized to 20-785 [4-(3-t-butylaminopropoxy)-2-carboxyl indole]. Bopindolol produces sustained blockade of beta 1- and beta 2-adrenoceptors, has intrinsic sympathomimetic as well as membrane stabilizing actions, inhibits renin secretion, and interacts with 5-HT receptors. Bopindolol is used in the treatment of hypertension. In limited trials bopindolol has also successfully reduced symptoms in patients with angina pectoris, anxiety and essential tremor.

Frentizole, a nontoxic antiviral and immunosuppressive agent, was used clinically in rheumatoid arthritis and systemic lupus erythematosus. Frentizole was more effective in suppressing human lymphocytes responding to Con A and PWM, than it was in cells activated by PHA, specific antigen, or alloantigen. Methylprednisolone, on the other hand, was more inhibitory for cells stimulated by PHA, specific antigen, or alloantigen. Frentizole, even at super immunosuppressive doses, does not predispose the hose (mice) to Pseudomonas aeruginosa, Candida albicans, herpes simplex virus, or Ann Arbor influenza virus. Frentizole is an inhibitor of the Aβ-ABAD interaction.

Roquinimex (Linomide, LS 2616) is a quinoline-3-carboxamide with pleiotropic immune modulating capacity and it has therapeutic effects in several experimental animal models of autoimmune diseases. Linomide has been evaluated in clinical trials for multiple sclerosis, and was indeed shown to have disease inhibitory effects. However, due to unexpected side effects recorded in patients treated with Linomide, premature termination of clinical trials was required. The basic mechanism(s) of action of Linomide in inducing beneficial effects in autoimmune diseases is still elusive. Some experimental evidence indicates that Linomide influences the regulation of the cytokine profile, resulting in the inhibition of autoimmune and inflammation pathologies. Roquinimex possesses potential antineoplastic activity. Roquinimex inhibits endothelial cell proliferation, migration, and basement membrane invasion; reduces the secretion of the angiogenic factor tumor necrosis factor alpha by tumor-associated macrophages (TAMs); and inhibits angiogenesis. Roquinimex was in phase III clinical trials with Pharmacia Corporation in Europe and the US for the treatment of multiple sclerosis.

Amithiozone, also known as thioacetazone, is an oral antibiotic, which is used in the treatment of tuberculosis. In 1991, the World Health Organization (WHO) recommended replacing thioacetazone with ethambutol in patients with known or suspected HIV infection. Thioacetazone is no longer included in WHO’s recommended first-line treatment for tuberculosis and is now reserved for uncommon situations in which treatment options have been compromised by resistance to other anti-tuberculosis medicines in HIV-negative individuals. Despite the increased recognition of this risk, thioacetazone remained in use mainly in low-income countries because of its low cost. Amithiozone has also been used in trials studying the treatment of Mycobacterium Avium-intracellular Infection. One of the possible mechanism action of the drug is interference with the metabolism of methionine of susceptible tubercle bacilli, which utilize methionine for nucleic acid synthesis.