5. Reproductive And Post Reproductive Pharmacology Flashcards
What are the actions of oestrogen?
Mild anabolic Sodium and water retention Raises HDL, lowers LDL Decrease bone resorption Impair glucose tolerance Increase blood coagulability
What are the side effects of oestrogen?
Breast tenderness Nausea, vomiting Water retention Increased blood coagulability Thromboembolism Impaired glucose tolerance Endometrial hyperplasia and cancer Ovarian metaplasia and cancer Breast hyperplasia and cancer
What are the actions of progesterone?
Secretory endometrium Anabolic Increases bone mineral density Fluid retention Mood changes Maintains pregnancy
What are the side effects of progesterone?
Weight gain Fluid retention Anabolic Acne Nausea/vomiting Irritability, depression, PMS Lack of concentration
What are the actions/side effects of testosterone?
Male secondary sex characteristics Anabolic Acne Voice changes Increases aggression Metabolic
Give some oestrogen pharmacokinetics points
Natural and synthetic oestrogens well absorbed in GI tract
Also really absorbed from in and mucous membranes
Metabolised in liver
Excretion - in urine as glucuronides and sulfates
Give some progesterone pharmacokinetics points
Injected progesterone is bound to albumin with some stored in adipose tissue
Metabolised in liver
Metabolites excreted in urine conjugated to glucuronic acid
What are the adverse effects of the combined pill?
Risk of thromboembolism
Smoking increases this risk significantly
Also increases for long-term use in women over 35
Which enzyme metabolises COCP and POP in the liver?
CYP 450 enzymes
Which drugs can reduce efficacy of oral contraceptives?
Enzyme inducing drugs:
- anti-epileptic (carbamazepine or phenytoin)
- some antibiotics (rifampicin or rifabutin)
- some natural products (st johns wort)
Why can some drugs reduce efficacy of oral contraceptives?
They increase the production of hepatic CYP450
Why is HRT prescribed?
Symptoms - hot flushes, sweats, dyspareunia
Protect against risk of osteoporosis
What are the risks of HRT?
ERT - increases risk of developing endometrial and ovarian cancers
HRT - increases risk of developing breast cancer
Increase risk of venous thromboembolism
Cardiovascular disease
Increased risk of stroke
What are the treatments for osteoporosis?
Bisphosphonates
- class of frugs that reduce bone turnover
- act by controlling osteoclast activity
What are the pharmacokinetic considerations for osteoporosis treatments?
Long biological half life
Poor gut absorption
Absorption affected by food so must be taken on empty stomach
What are the adverse drug reactions to osteoporosis treatments?
Upper GI effects - oesophagitis
Hypocalcaemia - check calcium and vit D levels prior to initiating treatment
What is the action of mifepristone (RU486)?
Progesterone receptor antagonist
Acts as an anti-progesterone
Sensitising the myometrium to prostaglandin-induced contractions
Used for termination of pregnancy
What are selective estrogen receptor modulator (SERM)?
Pure agonists and pure antagonists in different tissues
What are drugs in the SERM class?
Tamoxifen
Raloxifene (treatment for osteoporosis)
What is the function of clomiphene?
Used in treatment of an ovulation
Competes with oestrogen for ER binding
Leads to ovulation induction through increased production of anterior pituitary hormones
What is tamoxifen?
A pro-drug - little affinity for the ER
Metabolised in liver to active derivatives
Active metabolites compete with oestrogen for binding to the ER
How does tamoxifen act in endometrium?
Acts as ER agonist
How does tamoxifen act in breast tissue?
Acts as ER antagonist
Binding of the ER following tamoxifen treatment causes cells to arrest the cell cycle
What is ulipristal acetate?
Selective progesterone receptor modulator
When used for emergency contraception the primary mode of action is thought most likely to be delay or inhibition of ovulation
Also effective treatment for uterine fibroids
