Ethionamide is a second-line agent, structurally similar to isoniazid, used as a second-line therapy for the treatment of multidrug-resistant tuberculosis or active tuberculosis in case of patient intolerance to other drugs. Depending on its the concentration at the infected site and the susceptibility of the infecting organism it may be bacteriostatic or bactericidal. When used alone rapidly develops bacterial resistance. Ethionamide was approved by FDA in 1965 as TRECATOR manufactured by Wyeth Pharmaceuticals Inc. (purchased by Pfizer in 2009). Ethionamide is specific for Mycobacteria and is thought to exert a toxic effect on mycolic acid components of the bacterial cell wall when activated through intermediate S-oxidation by EtaA. Mycolic acid synthesis was shown to be inhibited by ethionamide in the EthA protein-overexpressing mycobacteria,

Tranylcypromine is a non-hydrazine monoamine oxidase inhibitor with a rapid onset of activity. Tranylcypromine has being marketed under original trade name Parnate, indicated for the treatment of major depressive episode without melancholia. Tranylcypromine irreversibly and nonselectively inhibits monoamine oxidase (MAO). Within neurons, MAO appears to regulate the levels of monoamines released upon synaptic firing. Since depression is associated with low levels of monoamines, the inhibition of MAO serves to ease depressive symptoms, as this results in an increase in the concentrations of these amines within the CNS.

Betamethasone and its derivatives, betamethasone sodium phosphate and betamethasone acetate, are synthetic glucocorticoids. Used for its antiinflammatory or immunosuppressive properties, betamethasone is combined with a mineralocorticoid to manage adrenal insufficiency and is used in the form of betamethasone benzoate, betamethasone dipropionate, or betamethasone valerate for the treatment of inflammation due to corticosteroid-responsive dermatoses. Betamethasone and clotrimazole are used together to treat cutaneous tinea infections. Betamethasone is a glucocorticoid receptor agonist. This leads to changes in genetic expression once this complex binds to the GRE. The antiinflammatory actions of corticosteroids are thought to involve lipocortins, phospholipase A2 inhibitory proteins which, through inhibition arachidonic acid, control the biosynthesis of prostaglandins and leukotrienes. The immune system is suppressed by corticosteroids due to a decrease in the function of the lymphatic system, a reduction in immunoglobulin and complement concentrations, the precipitation of lymphocytopenia, and interference with antigen-antibody binding. Betamethasone binds to plasma transcortin, and it becomes active when it is not bound to transcortin.Betamethasone is used for: treating certain conditions associated with decreased adrenal gland function. It is used to treat severe inflammation caused by certain conditions, including severe asthma, severe allergies, rheumatoid arthritis, ulcerative colitis, certain blood disorders, lupus, multiple sclerosis, and certain eye and skin conditions.

Perphenazine is a relatively high potency phenothiazine that blocks dopamine 2 receptors predominantly, but also may possess antagonist actions at histamine 1 and cholinergic M1 and alpha 1 adrenergic receptors in the vomiting center leading to reduced nausea and vomiting. The drug was approved by FDA for the treatment of schizophrenia and control of severe nausea and vomiting (either alone or in combination with amitriptyline hydrochloride). Perphenazine is extensively hepatic to metabolites via sulfoxidation, hydroxylation, dealkylation, and glucuronidation; primarily metabolized by CYP2D6 to N-dealkylated perphenazine, perphenazine sulfoxide, and 7-hydroxyperphenazine (active metabolite with 70% of the activity of perphenazine) and excreted in the urine and feces.

Methylphenidate is a CNS stimulant approved for the treatment of narcolepsy and attention deficit hyperactivity disorder. The drug is believed to bind the dopamine transporter in the presynaptic cell membrane, thereby blocking the reuptake of dopamine and causing an increase in extracellular dopamine levels.

Metaraminol is a potent sympathomimetic amine that increases both systolic and diastolic blood pressure, is an adrenergic receptor alpha-1 agonist.. Metaraminol is indicated for prevention and treatment of the acute hypotensive state occurring with spinal anesthesia. It is also indicated as adjunctive treatment of hypotension due to hemorrhage, reactions to medications, surgical complications, and shock associated with brain damage due to trauma or tumor. Metaraminol is also used in the treatment of priapism, in spite of this application was not approved, it appears to be effective.

Levothyroxine (T4) is a synthetically prepared levo isomer of thyroxine, the major hormone secreted from the thyroid gland. Thyroxine is released from thyroglobulin by proteolysis and secreted into the blood. Thyroxine is peripherally deiodinated to form triiodothyronine (T3) which exerts a broad spectrum of stimulatory effects on cell metabolism. Thyroid hormone increases the metabolic rate of cells of all tissues in the body. In the fetus and newborn, thyroid hormone is important for the growth and development of all tissues including bones and the brain. In adults, thyroid hormone helps to maintain brain function, food metabolism, and body temperature, among other effects. The symptoms of thyroid deficiency relieved by levothyroxine include slow speech, lack of energy, weight gain, hair loss, dry thick skin and unusual sensitivity to cold. Levothyroxine acts like the endogenous thyroid hormone thyroxine (T4, a tetra-iodinated tyrosine derivative). In the liver and kidney, T4 is converted to T3, the active metabolite. In order to increase solubility, the thyroid hormones attach to thyroid hormone binding proteins, thyroxin-binding globulin, and thyroxin-binding prealbumin (transthyretin). Transport and binding to thyroid hormone receptors in the cytoplasm and nucleus then takes place. Thus by acting as a replacement for natural thyroxine, symptoms of thyroxine deficiency are relieved. Levothyroxine is used for use alone or in combination with antithyroid agents to treat hypothyroidism, goiter, chronic lymphocytic thyroiditis, myxedema coma, and stupor.

Leucovorin is a compound similar to folic acid, which is a necessary vitamin. It has been around and in use for many decades. Leucovorin is a medication frequently used in combination with the chemotherapy drugs fluoruracil and methotrexate. Leucovorin is not a chemotherapy drug itself, however it is used in addition to these chemotherapy drugs to enhance anticancer effects (with fluorouracil) or to help prevent or lessen side effects (with methotrexate). Leucovorin is also used by itself to treat certain anemia problems when folic acid deficiency is present.

Probenecid is the prototypical uricosuric agent. It inhibits the renal excretion of organic anions and reduces tubular reabsorption of urate. Probenecid has also been used to treat patients with renal impairment, and, because it reduces the renal tubular excretion of other drugs, has been used as an adjunct to antibacterial therapy. Probenecid is used for treatment of the hyperuricemia associated with gout and gouty arthritis. Probenecid is a uricosuric and renal tubular blocking agent. It inhibits the tubular reabsorption of urate, thus increasing the urinary excretion of uric acid and decreasing serum urate levels. Effective uricosuria reduces the miscible urate pool, retards urate deposition, and promotes resorption of urate deposits. Probenecid inhibits the tubular secretion of penicillin and usually increases penicillin plasma levels by any route the antibiotic is given. A 2-fold to 4-fold elevation has been demonstrated for various penicillins. Probenecid decreases both hepatic and renal excretion of sulfobromophthalein (BSP). The tubular reabsorption of phosphorus is inhibited in hypoparathyroid but not in euparathyroid individuals. Probenecid does not influence plasma concentrations of salicylates, nor the excretion of streptomycin, chloramphenicol, chlortetracycline, oxytetracycline, or neomycin.

Dimercaprol (2, 3-dimercapto-1-propanol) or British anti-Lewisite (BAL), is a colorless or almost colorless liquid chelating agent having a disagreeable, mercaptan-like odor. Dimercaprol was developed at Oxford University during World War II as a means of treating and reversing poisoning from Lewisite, an arsenical gas used in chemical warfare (and thus initially called British anti-Lewisite [BAL]). The sulfhydryl groups of dimercaprol form complexes with certain heavy metals thus preventing or reversing the metallic binding of sulfhydryl-containing enzymes. Parenterally administered dimercaprol is used to treat arsenic, gold, copper and mercury poisoning. It is indicated in acute lead poisoning when used concomitantly with edetate clcium disodium. Dimercaprol is occasionally used in the initial treatment of severe, symptomatic Wilson disease, but generally for a short time only.