Clomiphene (CLOMID®) is a triphenyl ethylene stilbene derivative which is an estrogen agonist or antagonist depending on the target tissue. It is an orally administered, nonsteroidal, ovulatory stimulant. Clomiphene (CLOMID®) is a mixture of two geometric isomers [cis (zuclomiphene) and trans (enclomiphene)] containing between 30% and 50% of the cis-isomer. Clomiphene (CLOMID®) initiates a series of endocrine events culminating in a preovulatory gonadotropin surge and subsequent follicular rupture. The first endocrine event in response to a course of clomiphene therapy is an increase in the release of pituitary gonadotropins. This initiates steroidogenesis and folliculogenesis, resulting in growth of the ovarian follicle and an increase in the circulating level of estradiol. Following ovulation, plasma progesterone and estradiol rise and fall as they would in a normal ovulatory cycle.

Gentamicin C1 is a part of gentamicin C complex, containing gentamicin C1, gentamicin C1a, and gentamicin C2 which compose approximately 80% of gentamicin and have been found to have the highest antibacterial activity. Commercial gentamicin C is a mixture of gentamicin C1, C1a, and C2. Gentamicin C1 has a methyl group in the 6' position of the 2-amino-hexose ring and is N methylated at the same position. Gentamicin is a broad spectrum aminoglycoside antibiotic. Aminoglycosides work by binding to the bacterial 30S ribosomal subunit, causing misreading of t-RNA, leaving the bacterium unable to synthesize proteins vital to its growth. Aminoglycosides are useful primarily in infections involving aerobic, Gram-negative bacteria, such as Pseudomonas, Acinetobacter, and Enterobacter. In addition, some mycobacteria, including the bacteria that cause tuberculosis, are susceptible to aminoglycosides. Infections caused by Gram-positive bacteria can also be treated with aminoglycosides, but other types of antibiotics are more potent and less damaging to the host. In the past the aminoglycosides have been used in conjunction with penicillin-related antibiotics in streptococcal infections for their synergistic effects, particularly in endocarditis. Aminoglycosides are mostly ineffective against anaerobic bacteria, fungi and viruses. Aminoglycosides like gentamicin "irreversibly" bind to specific 30S-subunit proteins and 16S rRNA. Specifically gentamicin binds to four nucleotides of 16S rRNA and a single amino acid of protein S12. This interferes with decoding site in the vicinity of nucleotide 1400 in 16S rRNA of 30S subunit. This region interacts with the wobble base in the anticodon of tRNA. This leads to interference with the initiation complex, misreading of mRNA so incorrect amino acids are inserted into the polypeptide leading to nonfunctional or toxic peptides and the breakup of polysomes into nonfunctional monosomes. Gentamicin complex is used for treatment of serious infections caused by susceptible strains of the following microorganisms: P. aeruginosa, Proteus species (indole-positive and indole-negative), E. coli, Klebsiella-Enterobactor-Serratia species, Citrobacter species and Staphylococcus species (coagulase-positive and coagulase-negative).

Colistin sulfate is a polypeptide antibiotic which penetrates into and disrupts the bacterial cell membrane. It is a cyclic polypeptide antibiotic from Bacillus colistinus. It is composed of Polymyxins E1 and E2 (or Colistins A, B, and C). Colistin was first isolated in Japan in 1949 from a flask of fermenting Bacillus polymyxa var. colistinus and became available for clinical use in 1959. The following local adverse events have been reported with topical corticosteroids, especially under occlusive dressings: burning, itching, irritation, dryness, folliculitis, hypertrichosis, etc. Healthcare providers had largely stopped using colistin in the 1970s because of its toxicity. However, with antibacterial resistance on the rise, colistin is increasingly being used today to treat severe, multidrug-resistant Gram-negative bacterial infections, particularly among intensive care-based patients. The problem with re-introducing an older drug, such as colistin, though, is that techniques for evaluating new drugs have evolved since the 1950s, and therefore, little is known about the dose needed to effectively fight infection while limiting the potential emergence of antimicrobial resistance and reducing potentially toxic side effects. More data are needed to guide optimal use of these older medications. An international team of NIAID-funded researchers is making progress in obtaining better dosing information about colistin and how best to use the antibiotic to treat Gram-negative bacterial infections. Resistance to colistin is rare. The first colistin-resistance gene that is carried in a plasmid and can be transferred between bacterial strains was described in 2016. This plasmid-borne mcr-1 gene has since been isolated in China, Europeand the United States.

Colistimethate is a methanesulfonate of polymyxin antibacterial colistin. Colistimethate is a nonactive prodrug. In aqueous solutions, colistimethate is hydrolyzed and forms a complex mixture of partially sulfomethylated derivatives and colistin. The antimicrobial activity of colistin is similar to that of polymyxin B and is restricted to gram-negative bacteria, including P aeruginosa, Acinetobacter species, Enterobacter-Klebsiella tribe, Escherichia coli, Salmonella and Shigella species, Citrobacter species, Yersinia pseudotuberculosis, Morganella morganii and Haemophilus influenzae. Colistin has also been shown to possess considerable in vitro activity against Stenotrophomonas maltophilia. Colistin and polymyxin B, however, do not have activity against Proteus, Providencia, Serratia species, Pseudomonas mallei, Burkholderia cepacia, Brucella species, most gram-positive bacteria, gram-negative cocci, anaerobes, fungi and parasites. Parenteral or nebulized colistimethate is indicated for the treatment of acute or chronic infections due to sensitive strains of certain gram-negative bacilli. It is particularly indicated when the infection is caused by sensitive strains of Pseudomonas aeruginosa.

Ergoloid mesylates (USAN), co-dergocrine mesilate (BAN) or dihydroergotoxine mesylate, trade name Hydergine, is a mixture of the methanesulfonate salts of three dihydrogenated ergot alkaloids (dihydroergocristine, dihydroergocornine, and alpha- and beta-dihydroergocryptine). It was developed by Albert Hofmann (the inventor of LSD) for Sandoz (now part of Novartis). Ergoloid mesylates act centrally, decreasing vascular tone and slowing the heart rate, and acts peripherally to block alpha-receptors. One other possible mechanism is the effect of ergoloid mesylates on neuronal cell metabolism, resulting in improved oxygen uptake and cerebral metabolism, thereby normalizing depressed neurotransmitter levels. Ergoloid Mesylate may increase cerebral metabolism and blood flow. The role of this medication in the therapy of dementia is controversial. A recent controlled study in patients with Alzheimer's disease found that there was no advantage to the use of ergoloid mesylates compared to placebo, suggesting that ergoloid mesylates may lower scores on some cognitive and behavioral rating scales. Further study is needed to determine the risk-benefit profile of ergoloid mesylates in the treatment of dementia.