16. Reproductive Pharmacology Flashcards
What receptors does oestrogen act on?
ERa and ERb
What are natural forms of therapeutic oestrogen?
Oestradiol
Oestriol
What are synthetic forms of oestrogen?
Mestranol
Stilbestrol
Ethinylestradiol
What are the clinical uses of oestrogen?
Contraception
Treat primary ovarian failure (eg. Turner’s syndrome)
Treat secondary ovarian failure (menopause)
What are the side effects of oestrogen?
Nausea, vomiting
Retention of salt and water, causing oedema and increased BP
Increased risk thromboembolism
Increased risk or uterine, ovarian and breast cancer
What are the contraindications of oestrogen?
Oestrogen dependent tumours Undiagnosed genital bleeding Liver disease History of thromboembolism Heavy smokers
What is Tamoxifen used for?
Oestrogen antagonist
Treat oestrogen positive breast cancer
What is Clomifene used for?
Oestrogen antagonist
Induces ovulation (used as fertility treatment)
Inhibits oestrogen binding in AP preventing normal negative feedback
Causes increased FSH and LH which stimulates ovaries
What are the actions of progesterone?
Maturation of endometrium Supports gestation and embryogenesis Increases insulin and insulin response Increases body temperature Depressant
Why are testosterone derivatives given instead of natural or derivatives of progesterone?
Naturally occurring are inactive orally
Derivatives must be delivered IM
Name 2 testosterone derivates
Norgestrel
Desogestrel
What are the clinical uses of progesteogens?
Contraception
HRT
Endometriosis
Endometrial cancer
What are the side effects of progestogens?
Weak androgenic action Fluid retention Weight changes Libido changes Depression PMS, irregular menstrual cycles Increased risk of thromboembolism
Name an anti-progestegen
Mifepristone
How does Mifepristone work?
Acts as a competitive receptor antagonist at the progesterone receptor
Name 2 drugs that could be part of a combined pill
Ethinylestradiol and norethisterone
What is the dosing of a combined pill?
Taken for 21 consecutive days and 7 hormone free days
What is the mechanism of action of a combined pill?
Oestrogen inhibits FSH release and development of the ovarian follicle
Progestogen inhibits LH release and prevents ovulation, makes cervical fluid inhospitable for sperm
What are the side effects of a combined pill?
Weight gain, nausea, mood changes, skin pigementation
Hypertension, breast cancer, thromboembolism
What is the mechanism of action of a progestogen-only pill?
Makes cervical mucous inhospitable to sperm
Inhibits LH release
Prevents ovulation
What medications can interfere with oral mediactions?
CYP-enzyme inducing antibiotics
Causes vomiting or diarrhoea
Seizure medication
St John’s wort
Name a progestogen-only injectable
Medroxyprogesterone
How often are progestogen only injectables administered?
Every 3 months
Not suitable for use for more than 2 years
Name a progestogen-only subdermal implant
Etonogestrel
