FRS Pharmacology Estrogen

Question 1

Drugs affecting the FRS

Answer 1

*1. Female Steroid Hormines e.g estrogen and progestins

2. Stimulants such as fertility drugs
3. Uterine contraction stimulants such as oxytocics
4. Abortion inducing drugs -Abortifacients
5. Gravid uterus relaxant drugs- tocolytics*

Question 2

Estrogens

Answer 2

• Prototype- Estradol
• synthesised by ovary and placenta
• small amounts by the testis and adrenal cortex, other tissues such as liver, fat , muslce, hair follicles convert steroid precursos to estrogen
• Endogerous form- Estradiol (Most potent),** Estrone** & Estriol
• Uses- small doses for hormonal therapy with blocked or absent ovary action
• Estradiol (estrace, climara)- oral contraceptive
• Premarin (conjugated estrogen)- post-menapause treatment

Question 3

Estrogen Therapeutic Action

Answer 3

• Development of FRS & Secondary sex characteristics
• Affects release of FSH & LH
• Causes capillary dilation, fluid retention, protein anabolism and thin cervical mucus
• Inhibits ovulation & prevent post-parttum breast discomfort
• Proliferation of endometrial lining
• Absence or decrease in estrogen produces signs and symptoms of menopause in uterus, vagina, breast and cervix

Question 4

Estrogen Indications

Answer 4

• Treatment of hypogonadism, castration & primary ovarian failure
• Prevents pospartum breast engorgement; in combination with progestins as oral contraceptive
• Retardation of osteoporosis in postmenapause

Hypogonadism in females describes the inadequate function of the ovaries, with impaired production of germ cells (eggs) and sex hormones (oestrogen and progesterone).

Question 5

Estrogen Pharmacokinetics

Answer 5

• Oral- absorbs via GIT
• Hepatic metabolism
• Excreted in urine
• cross placenta and enter breast milk
• Dont use if pregnant or lactating
• Onset-slow
• Peak- days
• Duration-unknown

Question 6

Estrogen Contraindications and Caution

Answer 6

• Presence of any known allergies
• Pregnancy
• Breast Cancer, vaginal bleeding and any estrogen dependent cancer
• History of thromboembolic disorder due to increased risk of thrombus and embolus development
• Caution- lactation (affects neonates and may cause hepatic dysfunction)

Question 7

Estrogen Adverse Effects

Answer 7

• Photosensitivity
• Peripheral Edema
• Chloasma hepatic aderoma
• nausea, vomiting
• change in nerves
• dysmenorrhea
• Corneal change

dysmenhorrea is throbbing or cramping pains in the lower abdomen.

Question 8

Estrogen Drug to Drug Interaction

Answer 8

• Serum Estrogen levels may decrease when given in combination with baribiturates, rifampin, tetracycline, phenytone. they increase hepatic metabolism of estrogen
• Toxic effect with corticosteroids
• Smoking- nicotine and estrogen increase thrombo and emboli risk
• grapefruit - increase serum levels by inhibting metabolism estradiols