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Showing 451 - 460 of 2633 results

Metyrapone (trade name Metopirone) is a drug used in the diagnosis of adrenal insufficiency and occasionally in the treatment of Cushing's syndrome (hypercortisolism). Metopirone, metyrapone USP, is an inhibitor of endogenous adrenal corticosteroid synthesis, available as 250-mg capsules for oral administration. The pharmacological effect of Metopirone is to reduce cortisol and corticosterone production by inhibiting the 11-β-hydroxylation reaction in the adrenal cortex. Removal of the strong inhibitory feedback mechanism exerted by cortisol results in an increase in adrenocorticotropic hormone (ACTH) production by the pituitary. With continued blockade of the enzymatic steps leading to production of cortisol and corticosterone, there is a marked increase in adrenocortical secretion of their immediate precursors, 11-desoxycortisol and desoxycorticosterone, which are weak suppressors of ACTH release, and a corresponding elevation of these steroids in the plasma and of their metabolites in the urine. These metabolites are readily determined by measuring urinary 17-hydroxycorticosteroids (17-OHCS) or 17-ketogenic steroids (17-KGS). Because of these actions, Metopirone is used as a diagnostic test, with urinary 17-OHCS measured as an index of pituitary ACTH responsiveness. Metopirone may also suppress biosynthesis of aldosterone, resulting in a mild natriuresis.
Glycopyrrolate is a synthetic anticholinergic agent with a quaternary ammonium structure. Glycopyrrolate is a muscarinic competitive antagonist used as an antispasmodic, in some disorders of the gastrointestinal tract, and to reduce salivation with some anesthetics. Glycopyrrolate binds competitively to the muscarinic acetylcholine receptor. Like other anticholinergic (antimuscarinic) agents, it inhibits the action of acetylcholine on structures innervated by postganglionic cholinergic nerves and on smooth muscles that respond to acetylcholine but lack cholinergic innervation. These peripheral cholinergic receptors are present in the autonomic effector cells of smooth muscle, cardiac muscle, the sinoatrial node, the atrioventricular node, exocrine glands and, to a limited degree, in the autonomic ganglia. Thus, it diminishes the volume and free acidity of gastric secretions and controls excessive pharyngeal, tracheal, and bronchial secretions. Glycopyrrolate antagonizes muscarinic symptoms (e.g., bronchorrhea, bronchospasm, bradycardia, and intestinal hypermotility) induced by cholinergic drugs such as the anticholinesterases. The highly polar quaternary ammonium group of glycopyrrolate limits its passage across lipid membranes, such as the blood-brain barrier, in contrast to atropine sulfate and scopolamine hydrobromide, which are highly non-polar tertiary amines which penetrate lipid barriers easily. Glycopyrrolate is marketed under the brand names Robinul, Robinul Forte, Cuvposa. In October 2015, glycopyrrolate was approved by the FDA for use as a standalone treatment for Chronic obstructive pulmonary disease (COPD), as Seebri Neohaler.
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.
Fluocinolone Acetonide is a corticosteroid that binds to the cytosolic glucocorticoid receptor. After binding the receptor the newly formed receptor-ligand complex translocates itself into the cell nucleus, where it binds to many glucocorticoid response elements (GRE) in the promoter region of the target genes. The DNA bound receptor then interacts with basic transcription factors, causing the increase in expression of specific target genes. The anti-inflammatory actions of corticosteroids are thought to involve lipocortins, phospholipase A2 inhibitory proteins which, through inhibition arachidonic acid, control the biosynthesis of prostaglandins and leukotrienes. Specifically glucocorticoids induce lipocortin-1 (annexin-1) synthesis, which then binds to cell membranes preventing the phospholipase A2 from coming into contact with its substrate arachidonic acid. This leads to diminished eicosanoid production. Cyclooxygenase (both COX-1 and COX-2) expression is also suppressed, potentiating the effect. In another words, the two main products in inflammation Prostaglandins and Leukotrienes are inhibited by the action of Glucocorticoids. Glucocorticoids also stimulate the lipocortin-1 escaping to the extracellular space, where it binds to the leukocyte membrane receptors and inhibits various inflammatory events: epithelial adhesion, emigration, chemotaxis, phagocytosis, respiratory burst and the release of various inflammatory mediators (lysosomal enzymes, cytokines, tissue plasminogen activator, chemokines etc.) from neutrophils, macrophages and mastocytes. Additionally 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. Like other glucocorticoid agents Fluocinolone acetonide acts as a physiological antagonist to insulin by decreasing glycogenesis (formation of glycogen). It also promotes the breakdown of lipids (lipolysis), and proteins, leading to the mobilization of extrahepatic amino acids and ketone bodies. This leads to increased circulating glucose concentrations (in the blood). There is also decreased glycogen formation in the liver. Fluocinolone Acetonide is used for the relief of the inflammatory and pruritic manifestations of corticosteroid-responsive dermatoses. Also for the treatment of chronic non-infectious uveitis affecting the posterior segment of the eye (Retisert). Preparations containing Fluocinolone Acetonide were first marketed under the name Synalar.

Class (Stereo):
CHEMICAL (MIXED)


Conditions:

Methohexital is an ultrashort-acting barbiturate widely used in dentistry because of its rapid onset, predictable effects, and short duration of action. It was marked under the name brevital sodium for the intravenous anaesthesia. It has also been commonly used to induce deep sedation. Like other barbiturates, methohexital exerts its effects through the gamma-aminobutyric acid (GABA) receptor complex. By binding to its own receptor on the complex, methohexital augments the inhibitory effect of GABA on neurons and additionally can exert a similar effect independent of GABA.
Chlordiazepoxide (trade name Librium) is a sedative and hypnotic medication of the benzodiazepine class. Chlordiazepoxide is indicated for the management of anxiety disorders or for the short-term relief of symptoms of anxiety, withdrawal symptoms of acute alcoholism, and preoperative apprehension and anxiety. Anxiety or tension associated with the stress of everyday life usually does not require treatment with an anxiolytic. The effectiveness of Librium in long-term use, that is, more than 4 months, has not been assessed by systematic clinical studies. Chlordiazepoxide acts on benzodiazepine allosteric sites that are part of the GABAA receptor/ion-channel complex and this results in an increased binding of the inhibitory neurotransmitter GABA to the GABAA receptor thereby producing inhibitory effects on the central nervous system and body similar to the effects of other benzodiazepines. Chlordiazepoxide act via micromolar benzodiazepine binding sites as Ca2+ channel blockers and significantly inhibit depolarization-sensitive Calcium uptake in animal nerve terminal preparations. The withdrawal of chlordiazepoxide during pregnancy and breastfeeding is recommended, as chlordiazepoxide rapidly crosses the placenta and also is excreted in breast milk. Chlordiazepoxide is a long-acting benzodiazepine drug. The half-life of Chlordiazepoxide is 5 – 30 hours but has an active benzodiazepine metabolite (desmethyldiazepam), which has a half-life of 36 – 200 hours. The necessity of discontinuing therapy because of undesirable effects has been rare. Drowsiness, ataxia and confusion have been reported in some patients — particularly the elderly and debilitated. While these effects can be avoided in almost all instances by proper dosage adjustment, they have occasionally been observed at the lower dosage ranges. In a few instances syncope has been reported.

Class (Stereo):
CHEMICAL (ACHIRAL)


Conditions:

Diphenoxylate is an opioid drug used for the treatment of acute diarrhea. The drug is used in combination with atropine and marketed under names Lomotil and Diphenoxylate hydrochloride and atropine sulfate. Diphenoxylate is biotransformed in man by ester hydrolysis to diphenoxylic acid (difenoxine), which is biologically active and the major metabolite in the blood. The drug exerts its action by activating mu opioid receptors of intestinal mucosa.
Medroxyprogesterone acetate (INN, USAN, BAN), also known as 17α-hydroxy-6α-methylprogesterone acetate, and commonly abbreviated as MPA, is a steroidal progestin, a synthetic variant of the human hormone progesterone. Medroxyprogesterone acetate (MPA) administered orally or parenterally in the recommended doses to women with adequate endogenous estrogen, transforms proliferative into secretory endometrium. Androgenic and anabolic effects have been noted, but the drug is apparently devoid of significant estrogenic activity. While parenterally administered MPA inhibits gonadotropin production, which in turn prevents follicular maturation and ovulation, available data indicate that this does not occur when the usually recommended oral dosage is given as single daily doses. MPA is a more potent derivative of its parent compound medroxyprogesterone (MP). While medroxyprogesterone is sometimes used as a synonym for medroxyprogesterone acetate, what is normally being administered is MPA and not MP. Used as a contraceptive and to treat secondary amenorrhea, abnormal uterine bleeding, pain associated with endometriosis, endometrial and renal cell carcinomas, paraphilia in males, GnRH-dependent forms of precocious puberty, as well as to prevent endometrial changes associated with estrogens. Progestins diffuse freely into target cells in the female reproductive tract, mammary gland, hypothalamus, and the pituitary and bind to the progesterone receptor. Once bound to the receptor, progestins slow the frequency of release of gonadotropin releasing hormone (GnRH) from the hypothalamus and blunt the pre-ovulatory LH surge.
Phentermine is an amphetamine that stimulates neurons to release or maintain high levels of a particular group of neurotransmitters known as catecholamines; these include dopamine and norepinephrine. High levels of these catecholamines tend to suppress hunger signals and appetite. The drug seems to inhibit reuptake of noradrenaline, dopamine, and seratonin through inhibition or reversal of the reuptake transporters. It may also inhibit MAO enzymes leaving more neurotransmitter available at the synapse. Phentermine (through catecholamine elevation) may also indirectly affect leptin levels in the brain. It is theorized that phentermine can raise levels of leptin which signal satiety. It is also theorized that increased levels of the catecholamines are partially responsible for halting another chemical messenger known as neuropeptide Y. This peptide initiates eating, decreases energy expenditure, and increases fat storage. Phentermine is indicated in the management of exogenous obesity as a short term (a few weeks) adjunct in a regimen of weight reduction based on caloric restriction. Phentermine hydrochloride is a sympathomimetic amine with pharmacologic activity similar to the prototype drugs of this class used in obesity, the amphetamines. Actions include central nervous system stimulation and elevation of blood pressure. Tachyphylaxis and tolerance have been demonstrated with all drugs of this class in which these phenomena have been looked for.
Cyclophosphamide (the generic name for Cytoxan, Neosar, Revimmune), also known as cytophosphane, is a nitrogen mustard alkylating agent, from the oxazophorines group. It is used to treat various types of cancer and some autoimmune disorders. It is a "prodrug"; it is converted in the liver to active forms that have chemotherapeutic activity