Session 5.1 - Sex steroids: reproductive health

Question 1

Bisphosphonates

Answer 1

Drug Class: Bisphosphonates

Mechanism of Action: Control osteoclast activity, reducing bone turnover

Common Indicators: Osteoporosis, Paget’s disease of the bone, Bone malignancy

ADRs: Oesophagitis, Hypocalcaemia

Important drug-drug rxns: Poor gut absorption - take on empty stomach

Question 2

Finasteride (what’s its MOA?)

Answer 2

MOA: 5 Alpha Reductase inhibitor, stopping conversion of testosterone into DHT

Question 3

Mifepristone

RU486

Answer 3

Drug Class: Progesterone receptor antagonist

Mechanism of Action: Anti-progesterone -> lining of womb breaksdown -> lost with embryo/foetus (Terminates pregnancy), Sensitizes Myometrium to Prostaglandin-induced contractions

Common Indicators: Abortion

Question 4

Clomiphene

Answer 4

Drug Class: Selective Estrogen Receptor Modulator (SERMs)

Mechanism of Action: Compete with Oestrogen for ER Binding in ovaries. Lead to ovulation induction through increased production of anterior pituitary hormones.

Question 5

Tamoxifen

Answer 5

Drug Class: Selective Estrogen Receptor Modulator (SERMs)

Mechanism of Action: It is a Prodrug. Metabolised in the liver to form active derivatives. Active derivatives compete with oestrogen to bind to ERs.

In endometrium –> Tamoxifen acts as ER agonist –> endometrial hyperplasia
In breast tissue –> Tamoxifen acts as ER antagonist –> cell cycle arrest

Question 6

Ulipristal acetate

Answer 6

Drug Class: Selective Progesterone Receptor Modulator

Mechanism of Action: Emergency contraception -> delays/inhibits ovulation

Indications: Emergency contraception, Uterine Fibroids

Question 7

State one adverse effect of COCP

Answer 7

Thromboembolism

Question 8

Why prescribe HRT?

Answer 8

• Reduce menopause symptoms
  eg. Hot flushes, sweats, dyspareunia
• Reduce risk of Osteoporosis
  (Oestrogen and Progesterone are good for bones)