Antiandrogens adverse effects

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. 

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... 

Gray, L.E., Jr., Wilson, V.S., Stoker, T., Lambright, C., Furr, J., Noriega, N., Howdeshell, K., Ankley, G.T., Luillette, L. (2006). Adverse effects of environmental antiandrogens and androgens on reproductive development in mammals. Environment, reproductive health and fertility. Int. J. Androl. 29(1) 96-104. 

Adverse effects and interactions are few in shortterm use. Minor complaints include headache, dizziness, constipation, diarrhoea, tiredness and muscular pain. Bradycardia and cardiac conduction defects may also occur. Cimetidine is a weak antiandrogen, and may cause gynaecomastia and sexual dysfunction in males. In the elderly particularly, it may cause CNS disturbances including lethargy, confusion and hallucinations. Cimetidine inhibits cytochromes P450, in particular CYP 1A2 and CYP 3A4 and there is potential for... 

The main varieties of adverse effects attributed to cimetidine relate to its antiandrogenic properties and its actions in sufficient concentrations on the central nervous system. There is also a spectrum of drug interactions, mainly attributable to inhibition of hepatic CYP isoforms, but they only have clinical consequences under special circumstances. Occasional adverse effects, which are generally minor, include bradycardia and conduction defects, thrombocytopenia, neutropenia, interstitial nephritis, mild hepatic dysfunction, and headache. Intestinal infection due to loss of the gastric acid barrier also occurs, and myalgia, fever, monoamine oxidase-Uke interactions, and neuropathies have been well documented occasionally. Allergic reactions, such as bronchospasm, have rarely been described. Anaphylaxis with recurrence on rechallenge is on record, as are asthma and skin effects. 

Flutamide is a non-steroidal antiandrogen that is used to treat prostatic cancer. Its most common adverse effects are liver damage and photosensitivity. 

Grey LE, Jr, Wilson VS, Stoker T, et al. Adverse effects of environmental antiandrogens and androgens on reproductive development in mammals. IntJAndrol 2006 29(1) 96-104. 

Adverse Effects of H2-Receptor Antagonists. The Hz-receptor antagonists are generally extremely safe drugs, with few adverse effects being reported. Cimetidine was shown to possess antiandrogen properties in a small number of patients however, this effect... 

Many commonly used drugs have sympatholytic, anticholinergic, sedative, or antiandrogenic effects that may exacerbate or contribute to the development of erectile dysfunction. Clinicians should be familiar with these agents and be prepared to make adjustments in drug regimens to minimize adverse effects of these drugs on a patient s erectile function. 

Themostcommon antiandrogen-related adverse effects are listed in Table 128-5. In the only randomized comparison of bicalntamide plus an LH-RH agonist versus flutamide plus an LH-RH agonist, diarrhea was more common in flutamide-treated patients. Antiandrogens can reduce the symptoms from the flare phenomenon associated with LH-RH agonist therapy. 

Antiandrogenic and progestational symptoms such as gynecomastia, impotence and menstrual irregularities related to the clinical use of spironolactone were observed already at a very early stage [7], and recognized since 1975 as characteristic adverse effects due to the unspecific interactions of spironolactone with the AR and PR [8]. 

Ask K, Dijols S, Giroud C, et al. Reduction of nilutamide by NO synthases implications for the adverse effects of this nitroaromatic antiandrogen drug. Chem Res Toxicol 2003 16 1547-1554. 

They have a low incidence of adverse reactions and the reactions that occur are generally mild. Rapid intravenous infusion of H2 antagonists may cause bradycardia. Cimetidine is more inclined to cross the blood-brain barrier and CNS effects such as somnolence and confusion have been described, especially in the elderly and in patients with impaired renal function. Cimetidine in high doses, as the only one of its class, has antiandrogenic effects which could be explained by an increase of prolactin secretion, binding to androgen receptors and inhibition the cytochrome P450 mediated hydroxylation of estradiol. 

Normal sexual activity is associated with ovulation in most female mammals. Compounds affecting this process can adversely affect female libido. Ovarian failure induced by xenobiotic compounds has been associated with a decrease in libido in women. Certain types of oral contraceptives as well as drugs of abuse (methadone, cannabis, alcohol) cause decreases in female libido. The treatment for hirsutism, excessive growth of hair in both normal and abnormal locations, is the compound cyproterone acetate. It is an antiandrogen that has the side effect of severely decreasing libido in women. 

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