Lomustine is used in the treatment of certain neoplastic diseases. Although it is generally agreed that lomustine alkylates DNA and RNA, it is not cross resistant with other alkylators. As with other nitrosoureas, it may also inhibit several key enzymatic processes by carbamoylation of amino acids in proteins. Common adverse reactions include delayed myelosupression, nausea, vomiting, stomatitis, and alopecia.

Amikacin, USP (as the sulfate) is a semi-synthetic aminoglycoside antibiotic derived from kanamycin. Amikacin "irreversibly" binds to specific 30S-subunit proteins and 16S rRNA. Amikacin inhibits protein synthesis by binding to the 30S ribosomal subunit to prevent the formation of an initiation complex with messenger RNA. Specifically Amikacin 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. Amikacin is used for short-term treatment of serious infections due to susceptible strains of Gram-negative bacteria, including Pseudomonas species, Escherichia coli, species of indole-positive and indole-negative Proteus, Providencia species, Klebsiella-Enterobacter-Serratia species, and Acinetobacter (Mima-Herellea) species. Amikacin may also be used to treat Mycobacterium avium and Mycobacterium tuberculosis infections. Amikacin was used for the treatment of gram-negative pneumonia.

Doxorubicin is an antineoplastic in the anthracycline class. General properties of drugs in this class include: interaction with DNA in a variety of different ways including intercalation (squeezing between the base pairs), DNA strand breakage and inhibition with the enzyme topoisomerase II. Most of these compounds have been isolated from natural sources and antibiotics. However, they lack the specificity of the antimicrobial antibiotics and thus produce significant toxicity. The anthracyclines are among the most important antitumor drugs available. Doxorubicin is widely used for the treatment of several solid tumors while daunorubicin and idarubicin are used exclusively for the treatment of leukemia. Doxorubicin may also inhibit polymerase activity, affect regulation of gene expression, and produce free radical damage to DNA. Doxorubicin possesses an antitumor effect against a wide spectrum of tumors, either grafted or spontaneous. Doxorubicin is used to produce regression in disseminated neoplastic conditions like acute lymphoblastic leukemia, acute myeloblastic leukemia, Wilms’ tumor, neuroblastoma, soft tissue and bone sarcomas, breast carcinoma, ovarian carcinoma, transitional cell bladder carcinoma, thyroid carcinoma, gastric carcinoma, Hodgkin’s disease, malignant lymphoma and bronchogenic carcinoma in which the small cell histologic type is the most responsive compared to other cell types. Doxorubicin is also indicated for use as a component of adjuvant therapy in women with evidence of axillary lymph node involvement following resection of primary breast cancer.

Fenfluramine (former brand names Pondimin, Ponderax and Adifax), also known as 3-trifluoromethyl-N-ethylamphetamine, is an anorectic that is no longer marketed. In combination with phentermine, it was part of the anti-obesity medication Fen-phen. Fenfluramine was introduced on the U.S. market in 1973 and withdrawn in 1997. It is the racemic mixture of two enantiomers, dexfenfluramine, and levofenfluramine. The drug increases the level of serotonin, a neurotransmitter that regulates mood, appetite and other functions. Fenfluramine causes the release of serotonin by disrupting vesicular storage of the neurotransmitter and reversing serotonin transporter function. The drug was withdrawn from the U.S. market in 1997 after reports of heart valve disease and pulmonary hypertension, including a condition known as cardiac fibrosis. It was subsequently withdrawn from other markets around the world. In this small exploratory and retrospective study, remarkably good results were reported on the use of fenfluramine as an add-on medication for controlling seizures in patients with the Dravet syndrome. The side effects were rare and nonserious and did not result in termination of the treatment. It is possible that this drug may have anticonvulsive effects for other severe epilepsy syndromes, especially in those characterized by photosensitive or induced seizures.

Dimethyl sulfoxide (DMSO) is a clear odorless liquid, inexpensively produced as a by-product of the paper industry. It is widely available in the USA as a solvent but its medical use is currently restricted by the FDA to the palliative treatment of interstitial cystitis and to certain experimental applications. In medicine, DMSO is also used as a topical analgesic, a vehicle for topical application of pharmaceuticals, as an anti-inflammatory, and an antioxidant.

Naloxone, sold under the brand name Narcan among others, is a medication used to block the effects of opioids, especially in overdose. Naloxone has an extremely high affinity for μ-opioid receptors in the central nervous system (CNS). Naloxone is a μ-opioid receptor (MOR) inverse agonist, and its rapid blockade of those receptors often produces rapid onset of withdrawal symptoms. Naloxone also has an antagonist action, though with a lower affinity, at κ- (KOR) and δ-opioid receptors (DOR). If administered in the absence of concomitant opioid use, no functional pharmacological activity occurs (except the inability for the body to combat pain naturally). In contrast to direct opiate agonists, which elicit opiate withdrawal symptoms when discontinued in opiate-tolerant people, no evidence indicates the development of tolerance or dependence on naloxone. The mechanism of action is not completely understood, but studies suggest it functions to produce withdrawal symptoms by competing for opiate receptor sites within the CNS (a competitive antagonist, not a direct agonist), thereby preventing the action of both endogenous and xenobiotic opiates on these receptors without directly producing any effects itself. When administered parenterally (e.g. intravenously or by injection), as is most common, naloxone has a rapid distribution throughout the body. The mean serum half-life has been shown to range from 30 to 81 minutes, shorter than the average half-life of some opiates, necessitating repeat dosing if opioid receptors must be stopped from triggering for an extended period. Naloxone is primarily metabolized by the liver. Its major metabolite is naloxone-3-glucuronide, which is excreted in the urine. Naloxone is useful both in acute opioid overdose and in reducing respiratory or mental depression due to opioids. Whether it is useful in those in cardiac arrest due to an opioid overdose is unclear. Naloxone is poorly absorbed when taken by mouth, so it is commonly combined with a number of oral opioid preparations, including buprenorphine and pentazocine, so that when taken orally, just the opioid has an effect, but if misused by injecting, the naloxone blocks the effect of the opioid. In a meta-analysis of people with shock, including septic, cardiogenic, hemorrhagic, or spinal shock, those who received naloxone had improved blood flow. Naloxone is also experimentally used in the treatment for congenital insensitivity to pain with anhidrosis, an extremely rare disorder (one in 125 million) that renders one unable to feel pain or differentiate temperatures. Naloxone can also be used as an antidote in overdose of clonidine, a medication that lowers blood pressure.

Esketamine is an S(+)-enantiomer of ketamine. It is a nonselective, noncompetitive antagonist of N-methyl-D-aspartate (NMDA) receptor. A nasal spray, containing esketamine, was approved in 2019 for the treatment of treatment-resistant depression in adults, in conjunction with an oral antidepressant, and is marketed under tradename SPARAVATO. Esketamine is a schedule III drug product in the USA.

Amantadine hydrochloride has pharmacological actions as both an anti-Parkinson and an antiviral drug. The mechanism by which amantadine exerts its antiviral activity is not clearly understood. It appears to mainly prevent the release of infectious viral nucleic acid into the host cell by interfering with the function of the transmembrane domain of the viral M2 protein. In certain cases, amantadine is also known to prevent virus assembly during virus replication. It does not appear to interfere with the immunogenicity of inactivated influenza A virus vaccine. The mechanism of action of amantadine in the treatment of Parkinson's disease and drug-induced extrapyramidal reactions is not known. Data from earlier animal studies suggest that amantadine hydrochloride may have direct and indirect effects on dopamine neurons. More recent studies have demonstrated that amantadine is a weak, non-competitive NMDA receptor antagonist (K1 = 10µM). Although amantadine has not been shown to possess direct anticholinergic activity in animal studies, clinically, it exhibits anticholinergic-like side effects such as dry mouth, urinary retention, and constipation. Amantadine was approved by the FDA in 1966 as a prophylactic agent against Asian influenza, and eventually received approval for the treatment of influenza virus A in adults. In 1969, it was also discovered by accident to help reduce symptoms of Parkinson's disease, drug-induced extrapyramidal syndromes, and akathisia.

Acetylcholine is the neurotransmitter at neuromuscular junctions, at synapses in the ganglia of the visceral motor system, and at a variety of sites within the central nervous system. Whereas a great deal is known about the function of cholinergic transmission at the neuromuscular junction and at ganglionic synapses, the actions of acetylcholine in the central nervous system are not as well understood. Cholinergic system is an important system and a branch of the autonomic nervous system which plays an important role in memory, digestion, control of heart beat, blood pressure, movement and many other functions. Acetylcholine in the brain alters neuronal excitability, influences synaptic transmission, induces synaptic plasticity, and coordinates firing of groups of neurons. Miochol®-E (acetylcholine chloride intraocular solution) is used to obtain miosis of the iris in seconds after delivery of the lens in cataract surgery, in penetrating keratoplasty, iridectomy and other anterior segment surgery where rapid miosis may be required.

Doxapram is an analeptic agent (a stimulant of the central nervous system). The respiratory stimulant action is manifested by an increase in tidal volume associated with a slight increase in respiratory rate. A pressor response may result following doxapram administration. Provided there is no impairment of cardiac function, the pressor effect is more marked in hypovolemic than in normovolemic states. The pressor response is due to the improved cardiac output rather than peripheral vasoconstriction. Following doxapram administration, an increased release of catecholamines has been noted. Doxapram produces respiratory stimulation mediated through the peripheral carotid chemoreceptors. It is thought to stimulate the carotid body by inhibiting certain potassium channels. Used as temporary measure in hospitalized patients with acute respiratory insufficiency superimposed on chronic obstructive pulmonary disease.