ATC G — Genito-urinary system and sex hormones

Flibanserin is an oral medication approved by the FDA in 2015 for hypoactive sexual desire disorder (HSDD) in premenopausal women. Marketed as Addyi, it acts on serotonin and dopamine receptors and is taken daily at bedtime.

Drospirenone is a fourth-generation progestogen with anti-mineralocorticoid and anti-androgen activity. It is widely used in combined oral contraceptives (Yaz, Yasmin) and in a progestogen-only pill (Slynd), often preferred for premenstrual symptoms and acne.

Levonorgestrel is a synthetic progestin used as emergency contraception (single 1.5mg dose), in combined oral contraceptives, hormonal IUDs and progestin-only pills. Most effective for emergency use within 72 hours of unprotected intercourse.

Testosterone is the principal androgen in men, used clinically as replacement therapy for confirmed hypogonadism. It is available as topical gels, injectable esters, transdermal patches and subcutaneous pellets, with selection driven by patient preference and monitoring needs.

Ethinyl estradiol is the synthetic estrogen used in nearly all combined hormonal contraceptives — pills, patches and vaginal rings. Its high oral potency and long duration make it suitable for once-daily contraceptive dosing combined with a progestin. It is on the WHO Essential Medicines List.

Estradiol is the principal natural estrogen in women, used as bioidentical hormone replacement therapy for menopausal symptoms and prevention of osteoporosis. It is available as oral tablets, transdermal patches and gels, vaginal creams, rings and tablets, allowing dose and route to be tailored.

Estriol is the weakest of the three natural estrogens, used primarily as topical vaginal therapy (Ovestin cream, pessaries) for postmenopausal urogenital atrophy. Its weak systemic effect and short half-life make it suited for local relief with minimal systemic exposure.

Conjugated estrogens are a mixture of estrogen sulfates derived from pregnant mare urine, used in postmenopausal hormone replacement therapy. Available as oral tablets and topical formulations, marketed primarily as Premarin.

Tibolone is a synthetic steroid for postmenopausal HRT with tissue-selective estrogenic, progestogenic and weak androgenic activity. It is widely available in Europe (Livial) but not approved in the United States; one tablet daily covers combined HRT in a single molecule.

Medroxyprogesterone acetate (MPA) is a synthetic progestin used as oral therapy (Provera) for menstrual cycle disorders and as part of menopausal HRT, and as a long-acting injectable contraceptive (Depo-Provera) given every 12 weeks. It has anti-estrogenic and anti-gonadotrophic effects.

Progesterone is a natural female sex hormone used as bioidentical replacement in menopausal hormone therapy (in combination with estradiol), in luteal-phase support during IVF, and in selected gynaecological indications. Available as oral micronised capsules and vaginal gels, capsules or inserts.

Norethindrone is a first-generation oral progestin in clinical use since 1957. It is used in progestin-only contraceptive 'mini-pills', combined with ethinyl estradiol in many combined oral contraceptives, and as monotherapy at higher dose for abnormal uterine bleeding and endometriosis.

Clomiphene is a selective estrogen receptor modulator used to induce ovulation in selected women with anovulatory infertility. Taken as a 5-day course early in the menstrual cycle, typically under fertility specialist supervision.

Raloxifene is a selective estrogen receptor modulator (SERM) used for prevention of postmenopausal osteoporosis and reduction of invasive breast cancer risk. It activates estrogen receptors in bone while blocking them in breast and uterus, offering targeted benefit without HRT estrogenic effects.

Alprostadil is the prostaglandin E1 used for erectile dysfunction when oral PDE5 inhibitors are ineffective or contraindicated. It is administered as intracavernosal injection (Caverject, Edex) or as a urethral pellet (Muse), producing reliable erection within minutes through direct vasodilation.

Sildenafil citrate is a selective PDE5 inhibitor used in adult men for erectile dysfunction. It supports erections by raising cyclic GMP levels in penile tissue during sexual stimulation. Available under brand and generic names.

Tadalafil is a long-acting selective PDE5 inhibitor used for erectile dysfunction, benign prostatic hyperplasia and pulmonary arterial hypertension. Its 17-hour half-life supports an effect window of up to 36 hours. Available under brand and generic names.

Vardenafil is a selective PDE5 inhibitor used in adult men for erectile dysfunction. Its onset and effect window are similar to sildenafil, with a half-life of 4 to 5 hours. Marketed by Bayer as Levitra and as authorised generics.

Avanafil is the newest PDE5 inhibitor approved for erectile dysfunction (FDA 2012, marketed as Stendra in the US and Spedra in Europe). It offers faster onset and shorter duration than sildenafil or tadalafil, with a more selective enzyme profile that may reduce some side effects.

Dapoxetine is a short-acting selective serotonin reuptake inhibitor designed specifically for on-demand treatment of premature ejaculation in adult men. Unlike other SSRIs, it has rapid onset and short duration suitable for as-needed use.

Finasteride is a selective 5-alpha-reductase type II inhibitor used in male pattern hair loss (1mg) and benign prostatic hyperplasia (5mg). It reduces dihydrotestosterone production, slowing or partially reversing androgen-driven hair loss in men.

Dutasteride is a dual 5α-reductase inhibitor that blocks both type 1 and type 2 isoenzymes, reducing dihydrotestosterone (DHT) more completely than finasteride. It is used for benign prostatic hyperplasia and off-label for androgenetic alopecia.