Arbekacin is a broad-spectrum aminoglycoside used to treat methicillin-resistant Staphylococcus aureus (MRSA). Arbekacin has antibacterial activities against high-level gentamicin-resistant Enterococci, multidrug-resistant Pseudomonas aeruginosa, and Acinetobacter baumannii et al. In a cell-free system, habekacin (arbekacin) interfered with polypeptide synthesis, caused codon misreading, and inhibited translocation of N-acetylphenylalanyl-tRNA from the acceptor site to the donor site on ribosomes. Arbekacin bound to both 50S and 30S ribosomal subunits. Arbekacin has been approved as an injectable formulation in Japan since 1990, under the trade name Habekacin, for the treatment of patients with pneumonia and sepsis caused by MRSA. Meiji Seika Pharma is developing an inhaled aerosol formulation of arbekacin for the treatment of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia. Nobelpharma is developing an intravenous formulation of arbekacin sulfate, known as nonsense readthrough compound or NPC 14, for the treatment of Duchenne muscular dystrophy.

Ergosterol was discovered over 100 years ago in the plant pathogenic ergot fungus Claviceps purpurea. Ergosterol is the major fungal membrane sterol that regulates membrane fluidity, plasma membrane biogenesis and function. Antifungal drugs such as Amphotericin B exerts its action by simply binding ergosterol. Vitamin D2 (ergocalciferol) is derived from ergosterol by UVB irradiation. Ergocalciferol is used for treating low parathyroid hormone levels, rickets (a vitamin D deficiency condition), and low phosphate levels in the body.

Fenoterol is a beta2-adrenoreceptor agonist, used as a bronchodilator for the treatment and prevention of bronchospasms, associated with asthma and chronic obstructive airway disease, including bronchitis and pulmonary emphysema. Fenoterol is also used for tocolysis during premature labor. Marketing of fenoterol for treatment of asthma was suspended in Australia and New Zealand because of an increased risk of deaths, most likely due to excessive self-administration of the drug.

Methylnaltrexone bromide, (17s)- (methylnaltrexone bromide), a quaternary amine of the pure narcotic antagonist naltrexone, is a peripherally-acting selective mu-opioid antagonist. Methylnaltrexone antagonizes opioid binding at mu-opioid receptors, half-maximal inhibitory concentration (IC50) of 70 nM. It has a relatively lower affinity for κ-opioid receptors (IC50 575 nM), and it does not interact with δ-receptors or orphanin FQ receptors. Approved by FDA in the United States under the trade name Relistor, methylnaltrexone bromide is indicated for the treatment of opioid-induced constipation in patients with advanced illness who are receiving palliative care, when the response to laxative therapy has not been sufficient. Restricted ability to cross the blood-brain barrier allows methylnaltrexone bromide to function in tissues such as the gastrointestinal tract, decreasing the constipating effects of opioids without impacting opioid-mediated analgesic effects on the central nervous system.

Epidihydrocholesterin (Cholestanol) is a sterol that differs from cholesterol by the absence of a double bond in the B ring and, in humans, is present in far lower concentrations than cholesterol. Epidihydrocholesterin is reported as an ingredient of Presteron. Presteron is an anti-inflammatory drug. It was reported that Presteron had no side effects like steroids on oral administration and intramuscular injection in human. Presteron partly inhibited ovine COX-1 by 10.4%, but it did not inhibit human recombinant COX-2 at all. Presteron inhibits the action of bradykinin, a potent inflammatory mediator, by suppressing Ca2+ dependent cellular PLA2 (cPLA2) and/or secretory PLA2 (sPLA2), and COX-1, resulting in alleviation of inflammation.

Imidapril (Tanatril), through its active metabolite imidaprilat, acts as an ACE inhibitor to suppress the conversion of angiotensin I to angiotensin II and thereby reduce total peripheral resistance and systemic blood pressure (BP). In clinical trials, oral imidapril was an effective antihypertensive agent in the treatment of mild to moderate essential hypertension. Some evidence suggests that imidapril also improves exercise capacity in patients with chronic heart failure (CHF) and reduces urinary albumin excretion rate in patients with type 1 diabetes mellitus. Imidapril was well tolerated, with a lower incidence of dry cough than enalapril or benazepril, and is a first choice ACE inhibitor for the treatment of mild to moderate essential hypertension.

BQ-123 is a selective endothelin receptor-1 antagonist; it is used as a biochemical tool in the study of endothelin receptor function. BQ-123 was suspected to contribute to the regulation of vascular tone humans. However, a study involving young normotensive subjects did not demonstrate any major role for BQ-123 regulation of vascular tone.

Timepidium bromide is a quaternary ammonium antimuscarinic used for the symptomatic treatment of visceral spasms. It is a muscarinic antagonist.

Racecadotril (acetorphan) is an oral enkephalinase inhibitor for use in the treatment of acute diarrhea. Racecadotril reduces hypersecretion of water and electrolytes into the intestinal lumen, by preventing the degradation of endogenous enkephalins. Treatment with racecadotril reduces the incidence and duration of acute diarrhea and reduces diarrhea-associated symptoms compared with placebo in adults. Racecadotril treatment also results in significant reductions in stool output compared with placebo in infants and young children aged 2 months to 4 years with acute diarrhea. Both rotavirus-negative and rotavirus-positive infections appear to respond to treatment in the pediatric populations investigated for this infection. Racecadotril shows similar or slightly reduced efficacy to loperamide in the treatment of diarrhea in adults and children aged up to 10 years. However, in comparative trials, racecadotril was associated with fewer adverse events than loperamide, in particular, post-treatment constipation. Racecadotril is available in France (where it was first introduced in ~1990) and other European countries (including Germany, Italy, the UK, Spain and the Czech Republic) as well as most of South America and some South East Asian countries (including China, India and Thailand), but not in the United States.

Ramosetron (INN) is a serotonin 5-HT3 receptor antagonist for the treatment of nausea, vomiting. And "diarrhea-predominant irritable bowel syndrome in males" (IBS-D). Ramosetron is licensed for use in India, Japan (Iribo) and selected Southeast Asian countries. In animal studies, ramosetron reduced defecation induced by corticotrophin-releasing hormone and had inhibitory effects on colonic nociception. In two randomized controlled studies including 957 patients with IBS-D, ramosetron increased monthly responder rates of patient-reported global assessment of IBS symptom relief compared with placebo. Ramosetron was also as effective as mebeverine in male patients with IBS-D. In a recent randomized controlled trial with 343 male patients with IBS-D, ramosetron has proved effective in improving stool consistency, relieving abdominal pain/discomfort, and improving health-related quality of life. Regarding safety, ramosetron is associated with a lower incidence of constipation compared with other 5-HT3 receptor antagonists and has not been associated with ischemic colitis.