Corticosteroids properties

In low concentrations prepares uterus for blastocyst implantation promotes ovulation and mammary gland development regulates female sex accessory organs weak, corticosteroid properties precursor to sex hormones... 

The predominant clinical use of corticosteroids is a result of their associated antiinflammatory properties. These are commonly used as topicals for the suppression of symptoms, including inflammation, occurring in a particular disease state these compounds are rarely considered curative in their usage. Many other disease states do, however, respond well symptomatically to treatment with corticosteroid therapy. Some of these (11) are Hsted below. 

Efforts toward producing synthetic steroids, particularly cortisol, expanded during World War II to enable researchers to explore the possibiUty of medicinal appHcations of corticosteroids. In 1948, the discovery that cortisone dramatically alleviates the symptoms of arthritis led to intensive research on the antiinflammatory properties of corticosteroids. The development of partial and total syntheses for the commercial preparation of cortisone, alternative methods for producing cortisone, and the search for more potent antiinflammatory analogues gready stimulated both academic and industrial steroid research. 

Theophylline is also considered an alternative to inhaled corticosteroids for the treatment of mild persistent asthma however, limited efficacy compared to inhaled corticosteroids, a narrow therapeutic index with life-threatening toxicity, and multiple clinically important drug interactions have severely limited its use. Theophylline causes bronchodilation through inhibition of phosphodiesterase and antagonism of adenosine and appears to have anti-inflammatory and immunomodulatory properties as well.36... 

Corticosteroids have potent anti-inflammatory properties and are used in active IBD to rapidly suppress inflammation. Corticosteroids have favorable effects in modulating several cell types involved in the inflammatory process.20,21 They may be administered systemically or delivered locally to the site of action by altering the drug formulation (Table 16-2). Because these drugs usually improve symptoms and disease severity rapidly, they should be restricted to short-term management of active disease. Long-term use of systemic corticosteroids is... 

Clearly the physicochemical properties of a drug are a decisive factor in its overall activity. Where possible, molecular structures should be optimized to obtain best clinical performance. Rarely does an oral drug have physicochemical features suitable for topical or transdermal therapy, and it can take a great deal of systematic research to identify where the best balance of activity and permeability lies. Experience with corticosteroids suggests that as much as a 100-fold improvement in clinical activity may be attainable through molecular design, for today s most potent topical corticosteroids are more active than hydrocortisone by a factor at least this large. 

Corticosteroids have antiinflammatory and immunosuppressive properties. They interfere with antigen presentation to T lymphocytes, inhibit prostaglandin and leukotriene synthesis, and inhibit neutrophil and monocyte superoxide radical generation. 

The antiinflammatory properties of such topical agents as halcinonide are usually determined by a vasoconstrictor assay. Topically applied corticosteroids cause a blanching at the site of application, which can be the forearm or the upper back of healthy adults where stratum corneum is removed with cellophane tape. ° The test areas, containing various concentrations of halcinonide, are occluded with plastic wrap and are evaluated on an all-or-none basis. Percutaneous absorption studies with 0.1%... 

Corticosteroids (i.e., steroidal compounds) found in urine that possess biological properties resembling those of adrenal cortical extract, either in the increase or decrease of cholesterols levels,... 

Beclometasone is a corticosteroid. Corticosteroids are used as prophylaxis in patients with asthma and therefore have no use in an acute attack. Bronchodilators acting as relievers are indicated for an acute attack. In asthma, patients are advised first to administer the bronchodilator, which acts very fast and then apply the corticosteroid, which has anti-inflammatory properties. 

However, the spectrum of biological properties of many corticosteroids, as a rule, is much broader than the spectrum of properties present in clean glucocorticoids, as well as clean mineralocorticoids by definition. 

All corticosteroids are derivatives of cyclopentanophenanthrene with keto-groups at Cj and C20 and an unsaturated bond between C4 and C5 (indicated as A ), and the presence of an axial jS-CO-CH OH side chain at C j, which is absolutely necessary. They differ from one another in the presence of a keto- or 8-hydroxyl group at Cu, as well as on and/or Cig. These differences determine the major pharmacological properties of these drugs and their precursors. 

Corticosteroids do not heal illnesses, but they are widely used in various conditions when it is necessary to utilize their anti-inflammatory, immunosuppressant, and mineralo-corticoid properties. In addition, they are used in replacement therapy for patients who have adrenal insufficiency. Corticosteroids can be used in vital situations for asthma, severe allergic reactions, and transplant rejections. They are effective in noninfectious granulomatous diseases such as sarcoidosis, collagen vascular disease, rheumatoid arthritis, and leukemia. Steroids are used as lotions, ointments, etc. in treating a number of dermatological and ophthalmologic diseases. 

Pharmacokinetics The amount of corticosteroid absorbed from the skin depends on the intrinsic properties of the drug itself, the vehicle used, the duration of exposure, and the surface area and condition of the skin to which it is applied. 

Although corticosteroids possess immunosuppressive properties, their real value is in controlling the inflammation that can accompany transplantation and autoimmune disorders. Virtually all phases of the inflammatory process are affected by these drugs. Corticosteroid therapy alone is successful in only a limited number of autoimmune diseases, such as idiopathic thrombocytopenia, hemolytic anemia, and polymyalgia rheumatica. 

The first example of the influence of a fluorine atom on the biological properties of a molecule was for a family of corticosteroids. This discovery has very important applications on a medicinal level the use of fluorinated compounds to modify biological properties for therapeutic applications. 

Above all, Fried found out that introducing fluorine in corticosteroids had tremendous effects on their biological properties. After this discovery, this family of compounds became major drugs. 

Mechanism of Action Topical corticosteroids exhibit anti-inflammatory, antipruritic, and vasoconstrictive properties. Clinically, these actions correspond to decreased edema, erythema, pruritus, plaque formation, and scaling of the affected skin. Pharmacokinetics Approximately 3% is absorbed during an 8-hr period. Metabolized in the liver. Excreted in the urine. 

Mechanism of Action A topical corticosteroid that has anti-inflammatory, antipruritic, and vasoconstrictive properties. The exact mechanism of the anti-inflammatory process is unclear. Therapeutic Effect Reduces or prevents tissue response to the inflammatory process. 

The glucocorticoids also have powerful anti-inflammatory effects and when first introduced were considered to be the ultimate answer to the treatment of inflammatory arthritis. Although there are increasing data that low-dose corticosteroids have disease-modifying properties,... 

Glucocorticoids (corticosteroids) were the first hormonal agents recognized as having lympholytic properties. Administration of any glucocorticoid reduces the size and lymphoid content of the lymph nodes and spleen, although it has no toxic effect on proliferating myeloid or erythroid stem cells in the bone marrow. 

Dosing schedule Because of its physical properties, the skin acts as a reservoir for many drugs. As a result, the "local half-life" may be long enough to permit once-daily application of drugs with short systemic half-lives. For example, once-daily application of corticosteroids appears to be just as effective as multiple applications in many conditions. 

Tar preparations are used mainly in the treatment of psoriasis, dermatitis, and lichen simplex chronicus. The phenolic constituents endow these compounds with antipruritic properties, making them particularly valuable in the treatment of chronic lichenified dermatitis. Acute dermatitis with vesiculation and oozing may be irritated by even weak tar preparations, which should be avoided. However, in the subacute and chronic stages of dermatitis and psoriasis, these preparations are quite useful and offer an alternative to the use of topical corticosteroids. 

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