Trimetrexate, a second-generation folate antagonist which was used under brand name NEUTREXIN with concurrent leucovorin administration (leucovorin protection) was indicated as an alternative therapy for the treatment of moderate-to-severe Pneumocystis carinii pneumonia (PCP) in immunocompromised patients, including patients with the acquired immunodeficiency syndrome (AIDS). Nevertheless, this product was discontinued. In present time, trimetrexate with a different combinations is in the phase II of clinical trial for the treatment the following cancer diseases: pancreatic cancer and colorectal cancer (in combination with fluorouracil and leucovorin) and to treat a refractory acute leukemia in combination with leucovorin. Trimetrexate is a competitive inhibitor of dihydrofolate reductase (DHFR) from bacterial, protozoan, and mammalian sources. DHFR catalyzes the reduction of intracellular dihydrofolate to the active coenzyme tetrahydrofolate. Inhibition of DHFR results in the depletion of this coenzyme, leading directly to interference with thymidylate biosynthesis, as well as inhibition of folate-dependent formyltransferases, and indirectly to inhibition of purine biosynthesis. The result is disruption of DNA, RNA, and protein synthesis, with consequent cell death.

Trimetrexate, a second-generation folate antagonist which was used under brand name NEUTREXIN with concurrent leucovorin administration (leucovorin protection) was indicated as an alternative therapy for the treatment of moderate-to-severe Pneumocystis carinii pneumonia (PCP) in immunocompromised patients, including patients with the acquired immunodeficiency syndrome (AIDS). Nevertheless, this product was discontinued. In present time, trimetrexate with a different combinations is in the phase II of clinical trial for the treatment the following cancer diseases: pancreatic cancer and colorectal cancer (in combination with fluorouracil and leucovorin) and to treat a refractory acute leukemia in combination with leucovorin. Trimetrexate is a competitive inhibitor of dihydrofolate reductase (DHFR) from bacterial, protozoan, and mammalian sources. DHFR catalyzes the reduction of intracellular dihydrofolate to the active coenzyme tetrahydrofolate. Inhibition of DHFR results in the depletion of this coenzyme, leading directly to interference with thymidylate biosynthesis, as well as inhibition of folate-dependent formyltransferases, and indirectly to inhibition of purine biosynthesis. The result is disruption of DNA, RNA, and protein synthesis, with consequent cell death.

Altretamine is structurally similar to the alkylating agent triethylenemelamine (tretamine). Although Altretamine structurally resembles an alkylating agent, it has not been found to have alkylating activity in vitro. The precise mechanism of Altretamine cytotoxicity is unknown, although several proposals have been made. Altretamine requires N-demethylation in the liver to produce reactive intermediates (formaldehyde and/or iminium species) which covalently bind to DNA, resulting in DNA damage, or act as alkylating agents. Altretamine is used as a palliative treatment for persistent or recurrent ovarian cancer following treatment failure with a cisplatin- or alkylating agent-based combination. Side effects of Altretamine include nausea and vomiting, neurotoxicity (mood disorders, disorders of consciousness, ataxia, dizziness, vertigo), mild to moderate dose-related myelosuppression. Altretamine has been shown to be embryotoxic and teratogenic in rats and rabbits and may cause fetal damage when administered to a pregnant woman. Under the trade name Hexalen, Altretamine, is an antineoplastic agent. It is indicated for use as a single agent in the palliative treatment of patients with persistent or recurrent ovarian cancer following first-line therapy with a cisplatin and/or alkylating agent-based combination.

Methylparaben (E number E218) is preservative in the food, cosmetic, and pharmaceutical industries. It is completely absorbed through the skin or after ingestion and and it is hydrolyzed to para-hydroxybenzoic acid, and metabolites are rapidly excreted in the urine. Methylparaben is on the FDA generally regarded as safe list.

Cefoperazone (marketed under the name Cefobid) is a third-generation cephalosporin antibiotic. Cefoperazone has a broad spectrum of activity: Respiratory Tract Infections caused by S. pneumoniae, H. influenzae, S. aureus (penicillinase and non-penicillinase producing strains), S. pyogenes (Group A beta-hemolytic streptococci), P. aeruginosa, Klebsiella pneumoniae, E. coli, Proteus mirabilis, and Enterobacter species. Peritonitis and Other Intra-abdominal Infections caused by E. coli, P. aeruginosa, and anaerobic gram-negative bacilli (including Bacteroides fragilis). Bacterial Septicemia caused by S. pneumoniae, S. agalactiae, S. aureus, Pseudomonas aeruginosa, E. coli, Klebsiella spp., Klebsiella pneumoniae, Proteus species (indole-positive and indole-negative), Clostridium spp. and anaerobic gram-positive cocci. Infections of the Skin and Skin Structures caused by S. aureus (penicillinase and non-penicillinase producing strains), S. pyogenes, and P. aeruginosa. Pelvic Inflammatory Disease, Endometritis, and Other Infections of the Female Genital Tract caused by N. gonorrhoeae, S. epidermidis, S. agalactiae, E. coli, Clostridium spp., Bacteroides species (including Bacteroides fragilis), and anaerobic gram-positive cocci. Cefobid has no activity against Chlamydia trachomatis. Therefore, when Cefobid is used in the treatment of patients with pelvic inflammatory disease and C. trachomatis is one of the suspected pathogens, appropriate anti-chlamydial coverage should be added. Urinary Tract Infections caused by Escherichia coli and Pseudomonas aeruginosa. Cefoperazone, a third-generation cephalosporin, interferes with cell wall synthesis by binding to the penicillin-binding proteins (PBPs), thus preventing cross-linking of nascent peptidoglycan. Cefoperazone is stable to penicillinases and has a high degree of stability to many beta-lactamases produced by gram-negative bacteria. When tested in vitro, cefoperazone has demonstrated synergistic interactions with aminoglycosides against gram-negative bacilli. As with all cephalosporins, hypersensitivity manifested by skin reactions or drug fever. Reversible neutropenia may occur with prolonged administration. Diarrhea or loose stools has been reported also.

Niclosamide is an antihelminth used against tapeworm infections. It may act by the uncoupling of the electron transport chain to ATP synthase. The disturbance of this crucial metabolic pathway prevents creation of adenosine tri-phosphate (ATP), an essential molecule that supplies energy for metabolism. Niclosamide works by killing tapeworms on contact. Adult worms (but not ova) are rapidly killed, presumably due to uncoupling of oxidative phosphorylation or stimulation of ATPase activity. The killed worms are then passed in the stool or sometimes destroyed in the intestine. Niclosamide may work as a molluscicide by binding to and damaging DNA. Niclosamide is used for the treatment of tapeworm and intestinal fluke infections: Taenia saginata (Beef Tapeworm), Taenia solium (Pork Tapeworm), Diphyllobothrium latum (Fish Tapeworm), Fasciolopsis buski (large intestinal fluke). Niclosamide is also used as a molluscicide in the control of schistosomiasis. Niclosamide was marketed under the trade name Niclocide, now discontinued.

Cefoperazone (marketed under the name Cefobid) is a third-generation cephalosporin antibiotic. Cefoperazone has a broad spectrum of activity: Respiratory Tract Infections caused by S. pneumoniae, H. influenzae, S. aureus (penicillinase and non-penicillinase producing strains), S. pyogenes (Group A beta-hemolytic streptococci), P. aeruginosa, Klebsiella pneumoniae, E. coli, Proteus mirabilis, and Enterobacter species. Peritonitis and Other Intra-abdominal Infections caused by E. coli, P. aeruginosa, and anaerobic gram-negative bacilli (including Bacteroides fragilis). Bacterial Septicemia caused by S. pneumoniae, S. agalactiae, S. aureus, Pseudomonas aeruginosa, E. coli, Klebsiella spp., Klebsiella pneumoniae, Proteus species (indole-positive and indole-negative), Clostridium spp. and anaerobic gram-positive cocci. Infections of the Skin and Skin Structures caused by S. aureus (penicillinase and non-penicillinase producing strains), S. pyogenes, and P. aeruginosa. Pelvic Inflammatory Disease, Endometritis, and Other Infections of the Female Genital Tract caused by N. gonorrhoeae, S. epidermidis, S. agalactiae, E. coli, Clostridium spp., Bacteroides species (including Bacteroides fragilis), and anaerobic gram-positive cocci. Cefobid has no activity against Chlamydia trachomatis. Therefore, when Cefobid is used in the treatment of patients with pelvic inflammatory disease and C. trachomatis is one of the suspected pathogens, appropriate anti-chlamydial coverage should be added. Urinary Tract Infections caused by Escherichia coli and Pseudomonas aeruginosa. Cefoperazone, a third-generation cephalosporin, interferes with cell wall synthesis by binding to the penicillin-binding proteins (PBPs), thus preventing cross-linking of nascent peptidoglycan. Cefoperazone is stable to penicillinases and has a high degree of stability to many beta-lactamases produced by gram-negative bacteria. When tested in vitro, cefoperazone has demonstrated synergistic interactions with aminoglycosides against gram-negative bacilli. As with all cephalosporins, hypersensitivity manifested by skin reactions or drug fever. Reversible neutropenia may occur with prolonged administration. Diarrhea or loose stools has been reported also.

Iodamide is an ionic monomeric iodinated radiographic contrast medium. It was used in many procedures and may be given intravenously or by other routes, for example by instillation into the bladder or uterus; it has also been used for computed tomography. It is usually given as a 24 to 65% solution of the meglumine salt, or as a mixture of the sodium and meglumine salts; solutions of the sodium salt have also been used. Iodamide is no longer marketed in the US.

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.

Betahistine is an orally administered, centrally acting histamine H1 receptor agonist with partial H3 antagonistic activity. It is proposed that betahistine may reduce peripherally the asymmetric functioning of the sensory vestibular organs in addition to increasing vestibulocochlear blood flow by antagonising local H3 heteroreceptors. Betahistine acts centrally by enhancing histamine synthesis within tuberomammillary nuclei of the posterior hypothalamus and histamine release within vestibular nuclei through antagonism of H3 autoreceptors. This mechanism, together with less specific effects of betahistine on alertness regulation through cerebral H1 receptors, should promote and facilitate central vestibular compensation. Betahistine is used to treat the symptoms associated with Ménière's disease, a condition of the inner ear which causes, vertigo (dizziness), tinnitus (ringing in the ears), hearing loss.