Progestin megestrol acetate

Noncontraceptive Uses of Progestins. Progestins have other therapeutic uses aside from contraception. Hormone-dependent tumors and cysts involving reproductive tissues respond to progestins. Megestrol acetate and MPA are the two most commonly used progestins to treat breast cancer... 

Progestins Megestrol acetate Med roxyp rogestero ne 40 mg orally four times daily 400-1000 mg IM every week Weight gain, hot flashes, vaginal bleeding, edema, thromboembolism... 

High-dose progestins are used as last-line endocrine therapy [223]. They inhibit the adrenal steroid biosynthesis. The decrease of estrogen levels is comparable to that caused by the administration of aromatase inhibitors. In post-menopausal women, the progestin megestrol acetate (MGA) decreases serum plasma level of DEAH, androstenedione and cortisol to less than 10% [223,224]. 

Progesterone is synthesized in the corpus luteum in a cycle timed to the menstrual cycle. Synthesis continues should pregnancy develop. Progestins such as megestrol acetate and medroxyprogesterone acetate find use in therapy for metastatic breast cancer. 

Progestins, steroid compounds similar to progesterone, such as hydroxyprogesterone caproate (28.3.6), medroxyprogesterone acetate (28.3.7), and megestrol acetate (28.3.7), are used for palliative treatment of breast carcinomas and renal tumors. Progestins can have a direct local effect on cells, and can simultaneously lower the quantity of leutenizing hormone. 

Progestins have been used with some success in the treatment of breast cancer, and the response rate is approximately the same as with tamoxifen. Most clinical experience has been obtained using oral megestrol acetate. 

Megestrol acetate (see also Progestins Combined oral contraceptives) MelQ... 

Secondary adrenal insufficiency most commonly results from exogenous corticosteroid use, leading to suppression of the hypothalamic-pituitary-adrenal axis and decreased release of ACTH, resulting in impaired androgen and cortisol production. Mirtazapine and progestins (e.g., medroxyprogesterone acetate, megestrol acetate) have also been reported to induce secondary adrenal insufficiency. Secondary disease typically presents with normal mineralocorticoid concentrations. 

Progestins such as megestrol acetate and medroxyprogesterone acetate have been compared with tamoxifen in randomized trials and have been found to yield equal response rates. Although there were no direct comparisons of these two forms of progestational therapy, they appear to be equally effective. Medroxyprogesterone acetate is... 

The second structural class of steroidal progestins consists of pregnane derivatives like medroxyprogesterone acetate (MPA) (9), megestrol acetate (10) or cyproterone acetate (11). The introduction of a 17a-acetoxy group and different substituents in the 6-position of the parent molecule progesterone leads to an increase in metabolic stability and to orally active compounds. Cyproterone acetate was the first progestin... 

Megestrol acetate is a progestin that inhibits secretion of pituitary gonadotropins, thereby preventing follicular maturation and ovulation (contraceptive effect) inhibits spontaneous uterine contraction and transforms proliferative endometrium into secretory endometrium. It is indicated as a palliative treatment of advanced inoperable, recurrent, or metastatic carcinoma of breast or endometrium. 

Progestins Hydroxyprogesterone caproate, medroxyprogesterone acetate, megestrol acetate Endometrial, breast cancer... 

Esters [e.g., hydroxyprogesterone caproate (hyalutin) and MPA (DEPO-PROVERa)] are available for intramuscular administration, and MPA (PROVERA, others) and megestrol acetate (megace) may be used orally due to decreased hepatic metabolism. The 19-nor-steroids have good oral activity because the ethinyl substituent at C17 slows hepatic metabolism. Implants and depot preparations for prolonged release of synthetic progestins are widely available. 

Progestin activity is further enhanced when a doubie bond is introduced between positions 6 and 7, as is found in megestrol acetate (Fig. 46.13). Megestrol is used primarily in the treatment of breast and endometrial carcinomas and in postmenopausal women with advanced hormone-dependent carcinoma. Less than 10% of an oral dose undergoes metabolism. Several major metabolites appear in the urine (e.g., 2-hydroxy and 6-hydroxymethyl megestrol and their glucuronide conjugates). 

Mass Fragmentographic Method for the Determination of Megestrol Acetate in Plasma and Its Application to Studies on the Plasma Levels After Administration of the Progestin to Patients with Carcinoma Corporis Uteri J. Steroid Biochem. 5(7) 619-626 (1974) CA 83 4133g... 

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