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22 Cards in this Set
- Front
- Back
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Name androgens used in therapy
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Testosterone
Testosterone esters:testosterone enanthate, testosterone undecanoate 17a-alkylated androgens:Methyltestosterone, danazol |
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Indications for testosterone?
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Hypogonadism
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Indications for danazol?
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- Endometriosis- Hereditary angioedema- Hemophilia A- Immune thrombocytopenic purpura
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Mechanism of action of danazol?
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It increases the synthesis of C1q inhibitor, which is deficient in hereditary angioedema. It also enhances synthesis of factor VIII, treating hemophilia A.
It has also progestin activity, so it can bind to progesterone and androgen receptors in the pituitary and inhibit gonadotropin production. The inhibition is not strong enough to inhibit FSH and LH completely, but it is able to inhibit their mid-cycle peak secretion, inhibiting ovulation. This helps patients with endometriosis, menorrhagia and fibrocystic breats disease. |
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How is the pharmacokinetics of testosterone preparations?
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Almost all testosterone in plasma is bound to sex hormone binding globulin.
Testosterone undergoes first-pass metabolism and cant be taken orally. It has also a stort half-life. Testosterone esters have longer half-life 17-a alkylated testosterone can be taken orally. |
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How can testosterone be administrated?
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- Transdermal patch- Transdermal gel- Buccal system- Nasal gel
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Adverse effects of androgen preparations?
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Many...
Women: - Period disorders- Transformation to male secondary sex characteristics (hirtuism, clit enlargement, masculine voice) Men:- Reduced spermatogenesis due to inhibited FSH- Small testicles- Prostate hyperplasia- Gynecomastia Prepubertal boys:- Premature puberty- Premature closure of epiphyseal plates Fetus:- Dysgenesis of external genital organs Everyone:- Acne- Na+ and H2O retention- Hepatotoxic - danazol- Polycythemia- Increased muscle strenght but also pain- Increased LDL, decreased HDL- Aggressiveness, depression, psychosis |
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Name drugs used as anabolic steroids
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Testosterone, dihydrotestosterone, nandrolone, oxandrolone, trenbolone
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Why is taking anabolic steroids a problem?
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They are often taken in high doses and the side effects of androgens get much worse.
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Name the groups of antiandrogen drugs
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- Weak progestins- Androgen receptor antagonist- 5a-reductase inhibitors- Long-acting GnRH agonists and antagonists- Abiraterone
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Name weak progestins
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Cyproterone acetate, chlormadinone acetate
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Name androgen receptor antagonists
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Flutamide, nilutamide, spironolactone
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Name 5a-reductase inhibitors
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Finasteride, dutasteride
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Name long-acting GnRH agonists and antagonists
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- Leuprolide- Degarelix
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Indications of antiandrogens?
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- Hirtuism- Acne- Alopecia- Prostate hyperplasia - 5a-reductase- Prostate cancer- Premature puberty in boys
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Mechanism of action of cyproterone acetate?
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As weak progestin it inhbitis gonadotropin secretion, decresing synthesis of testosterone
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Mechanism of action of androgen receptor antagonists?
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They block androgen receptors. However, they inhibit negative feedback of testosterone on the hypothalamus and pituitary, which indirectly increases the testrosterone synthesis. For this reason they must be combined with GnRH agonists or antagonists |
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Mechanism of action of 5a-reductase inhibitors?
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They inhibit the conversion of testosterone into the more potent dihydrotestosterone in target tissues. This gives them an antiandrogen effect.
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Mechanism of action of abiraterone?
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Inhibits CYP17A1, which has two activities: 17a-hydroxylase and 17,20-lyase. These enzymes are involved in the synthesis of androgens, cortisol and estrogens.
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Mechanism of action of spironolactone as an antiandrogen?
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It blocks androgen receptors in addition to blocking mineralocorticoid receptors. It also inhibits 17a-hydroxylase
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Side effects of antiandrogens?
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- Gynecomastia- Tiredness- Reduced libido- Impotence- Increased hair growth
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Side effects of abiraterone?
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It increases the production of aldosterone indirectly due to re-routing the substrates of steroid hormones to produce aldosterone, instead of cortisol, androgen and estrogen. This causes:- Water retention- Hypertension- Hypokalemia |
