Contraceptives, HRT and SERMs Flashcards
Menopause
Permanent cessation of menstruation with loss of ovarian follicular activity
- average age 51 (range 45-55)
- lack of oestrogen production leads to increased LH and FSH levels as no negative feedback on hypothalamus and pituitary gland
Menopause complications
Oesteoporosis
- oestrogen (anabolic hormone) deficiency
- loss of bone matrix predisposing patients to osteoporotic fractures
- 10 fold increased fracture risk in post-menopausal woman
Cardiovascular disease
-CVD protection before menopause due to oestrogen-> menopause results in same risk as men by age of 70
Menopause symptoms
Typically diminish with time (bad at onset)
- Joint pain
- Hot flushes (head, neck, upper chest)
- Urogenital atrophy and dyspareunia
- Sleep disturbance
- Depression
- Decreased libido
Premature ovarian insufficiency
Menopause occurring before 40 years old (in 1% of women)->normal working of ovaries stops Causes: -autoimmune -surgery -chemotherapy -radiation
Tibolone
- synthetic prohormone
- oestrogenic, progestogenic and weak androgenic actions
- reduces fracture risk but increases risk of stroke and breast cancer
Raloxifene
- Selective Oestrogen Receptor Modulator
- Oestrogenic in bone (reducing vertebral fracture risk)
- Anti-oestrogenic in breast and uterus (reducing breast cancer risk)
- Does not reduce vasomotor symptoms
- Increased venous thromboembolism and fatal stroke risk
Tamoxifen
- Anti-oestrogenic on breast tissue
- Treats oestrogen-dependent breast tumours and metastatic breast cancers
Progesterone only contraceptive
- Used when oestrogens contraindicated (smoker, >35 years old, migraine with aura)
- Must be taken at same time each day (short half-life and short action duration)
- long acting preparations may be given via an intra-uterine system
Emergency contraception (post-coital)
Copper IUD
-intrauterine contraceptive device
-inserted within 5 (up to 7) days after unprotected intercourse
-affects sperm viability and function (spermicide)
-effectiveness not reduced in overweight/obese women
-most effective form of emergency contraception/birth control
Levonorgestrel
-used within 72 hours of intercourse but efficiency reduces with time so take asap
Ulipristal
-used within 120 hours of intercourse
-anti-progestin activity
-delays ovulation by as much as 5 days
-impairs implantation
Combined oral contraceptives?
- Oestrogen (ethinyl oestradiol) and Progesteron (Eg: levonorgestrel or norethisterone)
- take for 21 days (or 12 weeks), stop for 7 days
- Works by suppressing ovulation-> oestrogen and progesteron lead to negative feedback actions at hypothalamus/pituitary gland and progesteron thickens cervical mucus (hostile environment for sperm)
HRT
HORMONE REPLACEMENT THERAPY
-indicated use if debilitating vasomotor symptoms (controls these symptoms)
Types of HRT
- Oestrogen only
- Progestogen only
- Combined (oestrogen and progestogen)
HRT formulations
- can be adminstered cyclically whereby oestrogen is taken daily and for the last 12-14 days progesterone is taken
- can also be administered as continuous combined-> oestrogen and progesterone (little amounts) taken daily
Oestrogens
- Oestradiol: well absorbed but low bioavailability (extensive first pass metabolism from oral dose so higher dose administered orally)
- Estrone sulphate: ‘conjugated’ oestrogen
- Ethinyl estradiol: semi-synthetic oestrogen used in oral contraceptives. Ethinyl group protects molecule from first pass metabolism
MOST OESTROGENS CAN ALSO BE ADMINISTERED VIA TRANSDERMAL SKIN PATCHES
Sides effects of HRT
- Breast cancer
- Coronary heart disease
- Deep vein thrombosis
- Stroke
- Gallstones
However, the absolute risk of complications for healthy symptomatic postmenopausal women in their 50s taking HRT for 5 years is very low
