Antiandrogens bicalutamide

Antiandrogens bicalutamide cyproterone acetate flutamide nilutamide... 

Antiandrogens Bicalutamide Flutamide Nilutamide Inhibits the cellular uptake and effects of androgens in advanced, metastatic prostate cancer Nausea vomiting diarrhea decreased sex drive... 

The indole ring has also been reported as valuable carboxamide bioisoster (Figure 15.35b) of the non-steroidal antiandrogen bicalutamide. ... 

Modalities to prevent priapism are limited and not well studied. Pseudoephedrine (30 or 60 mg/day given orally at bedtime) and leuprolide, a gonadotropin-releasing hormone, have been used to decrease the number of recurrent episodes of priapism. Hydroxyurea therapy may also be useful. Recently, low-doses of an antiandrogen, bicalutamide, have been used in two patients with SCD and one patient with spinal cord injury for treatment of recurrent and refractory priapism without major side effects. " " ... 

In one of the few combination androgen-deprivation studies comparing two different antiandrogens (bicalutamide vs. flutamide), the time to treatment failure (the main study end point), time to progression (as defined by appearance of new or worsening bone or extraskeletal lesions), and time to death were equivalent, suggesting that the two treatments are equally effective. ... 

Yoshida, T., Kinoshita, H., Segawa, T., Nakamura, E., Inoue, T., Shimizu, Y., Kamoto, T. and Ogawa, O. (2005) Antiandrogen bicalutamide promotes tumor growth in a novel androgen-dependent prostate cancer xenograft model derived from a bicalutamide-treated patient. Cancer Research, 65, 9611-9616. 

Bicalutamide -nonsteroidal antiandrogen -endocrine effects -hot flashes -decreased libido -depression -weight gain -constipation... 

Monotherapy with flutamide, bicalutamide, and nilutamide is no longer recommended due to decreased survival as compared with patients treated with LHRH agonist therapy or orchiectomy. Antiandrogens are indicated for advanced prostate cancer only when combined with an LHRH agonist (flutamide and bicalutamide]) or orchiectomy (nilutamide). In combination, antiandrogens can reduce the LHRH agonist-induced flare. 

The adverse effects of antiandrogens are gynecomastia, hot flushes, GI disturbances, liver function test abnormalities, and breast tenderness. GI disturbances consist of diarrhea for flutamide and bicalutamide and nausea or constipation for nilutamide. Flutamide is also associated with methemoglobinemia, whereas nilutamide causes visual disturbances (impaired dark adaptation), alcohol intolerance, and interstitial pneumonitis. 

Bicalutamide, flutamide and nilutamide are nonsteroidal antiandrogens that are used for the treatment of prostatic carcinoma. They act as competitive antagonists at the androgen receptor. Hutamide also inhibits the formation of dihydrotestosterone from testosterone. 

The non-steroidal antiandrogens include flutamide, bicalutamide and nilutamide. By binding to the androgen receptor they inhibit translocation of the receptor from the cytoplasm to the nucleus. Flutamide also inhibits the formation of the active di-hydrotestosteron from testosteron. These agents are... 

Antiandrogens such as cyproterone acetate (5.54) or the nonsteroidal flutamide (5.55, a substituted anilide) are competitive antagonists on the cytosol receptor. They do not prevent DHT formation rather, they inhibit the nuclear retention of DHT in the prostate. They cause feminization in male fetuses and decrease libido in males. Cyproterone is also an active progestogen. In men, antiandrogens are used commonly in the treatment of prostatic cancer and uncommonly to inhibit sex drive in hypersexuality in women, antiandrogens are used to treat virilization. Bicalutamide (5.56) and nilutamide (5.57) are potent, orally active antiandrogens that may be used in the treatment of metastatic prostate carcinoma. 

Antiandrogens include steroids, such as cyprotcronc acetate, and non-steroidal agents, such as bicalutamide, fluta-mide, and nilutamide. They have different endocrine effects and therefore different adverse effects (1). Cyproterone acetate tends to result in a loss of sexual interest and erectile dysfunction, whereas most men experience this only moderately or not at all during nonsteroidal treatment. The most common adverse effects of the non-steroidal agents are gynecomastia and breast... 

Flutamide and bicalutamide are nonsteroidal antiandrogens available for use in conjunction with the gonadorelins (e.g. goserelin) in the treatment of prostatic carcinoma. Finasteride (p. 544), which inhibits conversion of testosterone to dihydrotestosterone, has localised antiandrogen activity in tissues where dihydrotestosterone is the principal androgen this makes it a useful drug in the treatment of benign prostatic hypertrophy. 

Antiandrogens Flutamide Bicalutamide Nilutamide Cyproterone acetate Progesterones 5-Of-Reductase inhibition Finasteride ... 

Three antiandrogens, flutamide, bicalutamide, and nilutamide, are currently available (Table 128-5). 

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