Drug Groups

approved

Description

Mometasone is a medium-potency synthetic corticosteroid with antiinflammatory, antipruritic, and vasoconstrictive properties. Studies in asthmatic patients have demonstrated that mometasone provides a favorable ratio of topical to systemic activity due to its primary local effect along with the extensive hepatic metabolism and the lack of active metabolites. Though effective for the treatment of asthma, glucocorticoids do not affect asthma symptoms immediately. Maximum improvement in symptoms following inhaled administration of mometasone furoate may not be achieved for 1 to 2 weeks or longer after starting treatment. he antiinflammatory actions of corticosteroids are thought to involve phospholipase A2 inhibitory proteins, lipocortins, which control the biosynthesis of potent mediators of inflammation such as prostaglandins and leukotrienes.

Indication

The inhaler is indicated for the maintenance treatment of asthma as prophylactic therapy. The nasal spray is indicated for the treatment of the nasal symptoms of seasonal allergic and perennial allergic rhinitis.

Pharmacology

Mometasone is a medium-potency synthetic corticosteroid with antiinflammatory, antipruritic, and vasoconstrictive properties. Studies in asthmatic patients have demonstrated that mometasone provides a favorable ratio of topical to systemic activity due to its primary local effect along with the extensive hepatic metabolism and the lack of active metabolites. Though effective for the treatment of asthma, glucocorticoids do not affect asthma symptoms immediately. Maximum improvement in symptoms following inhaled administration of mometasone furoate may not be achieved for 1 to 2 weeks or longer after starting treatment. When glucocorticoids are discontinued, asthma stability may persist for several days or longer. Mometasone has been shown in vitro to exhibit a binding affinity for the human glucocorticoid receptor which is approximately 12 times that of dexamethasone, 7 times that of triamcinolone acetonide, 5 times that of budesonide, and 1.5 times that of fluticasone. The clinical significance of these findings is unknown.

Toxicity

The potential for acute toxic effects following overdose with the mometasone inhaler is low. However, habitual overuse of the product can cause symptoms of steroid overload, including menstrual irregularities, acne, obesity, and muscle weakness. Single oral doses up to 8000 µg have been studied on human volunteers with no adverse events reported.

Affected Organisms

Biotransformation

Hepatic. Extensive metabolism to multiple metabolites. There are no major metabolites detectable in plasma. Upon in vitro incubation, one of the minor metabolites formed is 6ß-hydroxy-mometasone furoate. In human liver microsomes, the formation of the metabolite is regulated by cytochrome P-450 3A4.

Absorption

Nasal spray is virtually undetectable in plasma

Half Life

5.8 hours

Protein Binding

98% to 99% (in a concentration range of 5 to 500 ng/mL).

External Links