Rezatomidine (AGN 203818) is an alpha adrenergic receptor agonist that was developed for the treatment of chronic pain conditions. Phase II studies have evaluated the safety and effectiveness of rezatomidine in treating the pain in patients with fibromyalgia, irritable bowel syndrome, interstitial cystitis, and diabetic neuropathy. However, three studies were terminated early based on a business decision. Pancreatitis, gastric ulcer, viral infections and dehydration were reported as serious adverse events in patients when administered a 60mg dose.

Proflazepam is benzodiazepine derivative patented by Hoffmann-La Roche, F., und Co., A.-G. as anticonvulsant and muscle relaxant. In preclinical studies, Proflazepam shows activity in pentetrazole test and in the rotating rod test.

Caproxamine is 2-aminoethyl-oxime derivative patented by pharmaceutical company N. V. Philips' Gloeilampenfabrieken as the compound with pronounced action on the central nervous system in doses of 10-500 mg/day for adults.

Rispenzepine (DF 594) is a muscarinic receptor antagonist. Rispenzepine has high affinity for intestinal muscarinic receptors, with preferential action at M1 and M3 receptor subtypes. This drug shows potent inhibitory effects on intestinal motility. In guinea pigs, rispenzepine significantly increases acetylcholine release in the trachea. A phase II study to test efficacy in asthma patients has been discontinued.

Bremazocine, a kappa-opioid agonist has limited potential as a clinical analgesic, however, possesses a possible utility for the therapy of alcohol and drug addiction. It was shown that bremazocine-like drugs could lower intraocular pressure and to minimize ischemic damage, that could be used in the therapy of glaucoma and cardiovascular disease.

Strinoline is a quinoline derivative patented by Morton-Norwich Products, Inc. as antimycotic agent

Fenacetinol is an analgesic agent.

Fluradoline (also known as HP-494), a centrally acting antinociceptive agent with antidepressant properties. Experiments on rodents have shown that fluradoline blocked the reuptake of NE, 5-HT, and DA in the brain. Besides, fluradoline was studied for the prevention of acute and chronic postsurgical pain.

Betameprodine is an opioid analgesic under international control according to the UN Single Convention 1961. The stereoisomer alphameprodine was more widely used, however, had a similar classification.

Becampanel (AMP397) is an aminomethylquinoxalinedione AMPA receptor antagonist. Also, AMP397 demonstrates binding to hydroxyapatite. AMP397 has no genotoxic potential in vivo. In particular, no genotoxic metabolite is formed in mammalian cells, and, if formed by intestinal bacteria, is unable to exert any genotoxic activity in the adjacent intestinal tissue. AMP397 has a significant oral bioavailability of 22% in mice and approximately 50% in humans. It was under development for the potential treatment of status epilepticus and other types of seizures. However, this research has been discontinued. It is also being evaluated for use in the treatment of neuropathic pain and cerebrovascular ischemia.