Methenamine is an antibacterial agent for preventing recurrent urinary tract infection. It can be used as methenamine hippurate or methenamine mandelate preparations and is United States Food and Drug Administration-approved. Methenamine exerts its activity because it is hydrolyzed to formaldehyde in acid urine.

Spectinomycin is an antibiotic produced by Streptomyces spectabilis. It is active against gram-negative bacteria and used for the treatment of acute gonorrheal urethritis and proctitis in the male and acute gonorrheal cervicitis and proctitis in the female when due to susceptible strains of Neisseria gonorrhoeae. In vitro studies have shown spectinomycin to be active against most strains of Neisseria gonorrhoeae (minimum inhibitory concentration <7.5 to 20 mcg/mL). Footprint studies indicate that spectinomycin exerts regional effects on ribosomal structure. Spectinomycin hydrochloride is an inhibitor of protein synthesis in the bacterial cell; the site of action is the 30S ribosomal subunit. The antibiotic is not significantly bound to plasma protein. Spectinomycin was discovered 1961. It is on the World Health Organization's List of Essential Medicines, the most important medications needed in a basic health system. This antibiotic is no longer available in the United States. Pfizer has discontinued distribution of spectinomycin (Trobicin) in the U.S. The drug continues to be distributed outside the U.S.

Fusidic acid is a anti-bacterial agent, initially isolated from Fusidium coccineum by Godtfredsen et al (Leo Pharma) in 1960. It is discussed that fusidic acid exerts its anti-microbial effect by inhibiting bacterial elongation factor G, thus suppressing the protein synthesis. Fusidic acid is widely used in Europe under the names Fucidin H(fusidic acid / hydrocortisone acetate), Fucidin (fusidic acid / sodium fusidate) and Fucicort (fusidic acid / betamethasone valerate) for the treatment of primary/secondary skin infections and inflammatory dermatoses.

Mandelic acid is an aromatic alpha hydroxy acid that is used for the treatment of urinary tract infections. The drug is marketed in Canada under the name Mandelamine (as a complex with methenamine). Mandelic acid exerts its antibacterial effect mainly by increasing urine acidity. Moreover, mandelic acid is used as a serum for the treatment of wrinkles.

Clofoctol [2-(2,4-dichlorobenzyl)-4-(tetramethyl-1,1,3,3-butyl)phenol] is a synthetic antibacterial agent with bactericidal activity on various Gram-positive (especially S. pyogenes and S. pneumoniae, but also Corynebacterium spp. and Propionibacterium acnes) and some Gram-negative bacteria (including Haemophilus influenzae, Bordetella spp., Neisseria meningitides, and Neisseria gonorrhea). A peculiar property of clofoctol is the rapidity of the antimicrobial effect, similar to that of antiseptic compounds, which makes the development of resistance less likely. Following rectal administration of clofoctol, absorption is rapid and nearly complete (about 98%), with a good penetration in the lung tissue. Clofoctol is primarily metabolized by hepatic glucuronidation and excreted through the biliary system; renal elimination is negligible. Clofoctol compound has been used mainly in France (under the trade name Octoplus ) and Italy (as Gramplus) for the treatment of mild upper respiratory tract infections, especially in pediatric patients

Xibornol [6-(isoborn-2-yl)-3,4 xylenol] is a highly lipophilic and poorly soluble drug used as spray mouthwash for the local treatment of infection and inflammation of the throat and in the dental care, due to both its bacteriostatic activity, mainly against Gram positive micro-organisms and its antiviral properties. The drug concentration required for the therapeutic activity is 3% (w/v). Its poor water solubility makes difficult to set up drug formulations based on aqueous solvents, so xibornol is at present commercially available only as spray aqueous suspension. The self-microemulsifying approach was found to be effective to formulate stable and pharmaceutically acceptable liquid spray formulations of xibornol. The minimal inhibitory concentrations (MIC) and the minimal bactericidal concentrations (MBC) of xibornol against 100 strains of Staphylococcus aureus, clinically isolated have been evaluated in range between 2 ug/ml and 8 ug/ml. In the patients treated with xibornol (500 mg every 8 h for 7 days) any modification in phagocytosis frequency (PMF), phagocytosis index (PHI), nitroblue tetrazolium (NBT), reduction frequency (NRF), microbicidal activity and neutrophil mobility of PML, before, during and after the end of therapy wasn’t found.

Furagin (Furazidine) is a nitrofuran derivative, acting as an antibacterial medicine with bacteriostatic action. It is active against both gram-positive (Staphylococcus epidermidis, Staphylococcus aureus, Staphylococcus faecalis) and gram-negative microorganisms (Enterobacteriaceae – Salmonella, Shygella, Proteus, Klebsiella, Escherichia, Enterobacter, etc.). It is used for the treatment of urinary tract, skin and soft tissues infections.

Nifurtoinol, a nitrofuran-derivative, is an antibacterial drug. Nifurtoinol (Urfadyn PL) is used for the treatment of urinary tract infections. Nifurtoinol-associated hepatic injury cases were reported in Netherlands.

Ornidazole is nitroimidazole derivative. It is an antiprotozoal drug that has proven to be effective against Trichomonas vaginalis, Entoamoeba histolytica, Giardia lamblia and Helicobacter pylori. The reduction of the nitro group and the generation of short-lived reactive intermediates are the basis of its parasiticidal activity. Ornidazole is a DNA-tropic drug with selective activity against microorganisms with enzyme systems capable of reducing the nitrogroup and catalyze the interaction between ferrodoxin proteins and nitrocompounds. After the drug penetrates the microbial cell, the mechanism of its action is based reducing the nitrogroup under the influence of the microorganism’s nitroreductases and the activity of the reduced nitroimidazole. The reduction products create compounds with DNA causing it to degrade, and disrupt the DNA replication and transcription processes. Furthermore, the drug’s metabolism products have cytotoxic properties and disrupt cellular respiration processes. It is indicated for the treatment of anaerobic systemic infections caused by ornidazole-sensitive microflora, prevention of infections caused by anaerobic bacteria, during operative treatment (especially middle and straight intestine surgeries), gynecological surgeries, severe intestinal ameobiasis, all extra-intestinal ameobiasis forms, giardiasis. Ornidazole was shown to be effective for the prevention of recurrence of Crohn's disease after ileocolonic resection.

Nitroxoline (8-hydroxy-5-nitroquinoline) has been used since 1962 in the treatment of urinary tract infections especially those due to gram negative bacilli (E. coli). Nitroxoline is active against most Gram-negative and –positive uropathogenic bacteria, against mycoplasmas (M. hominis, Ureaplasma urealyticum) and human pathogenic Candida spp. The mode of antibacterial and antifungal action is based on the ability of nitroxoline to chelate with various metallic bivalent cations. Nitroxoline is a fluorquinolone that is active against bacterial gyrases. This drug may also have antitumor activity by inhibition of type 2 methionine aminopeptidase (MetAP2) protein which is involved in angiogenesis. Nitroxoline induces apoptosis and inhibits glioma growth in vivo and in vitro. Due to the excellent anticancer activity and its well-known safety profile and pharmacokinetic properties, nitroxoline has been approved to enter into a phase II clinical trial in China for non-muscle invasive bladder cancer treatment