Lecture 60: Pharmacology of Sex Hormones Flashcards
what are the 4 receptor superfamilies
- ligand-gated ion channels (ionotropic receptors)
- G-protein-coupled receptors (metabotropic)
- kinase-linked receptors
- nuclear receptors
give examples of ligand-gated ion channels (ionotropic receptors)
- nicotinic
- ACh receptor
give examples of G-protein-coupled receptors (metabotropic)
- muscarinic
- ACh receptor
give example of kinase-linked receptors
cytokine receptors
give example of nuclear receptors
oestrogen receptor
what receptor superfamily do sex hormones (steroids) bind to
superfamily 4 - nuclear receptors
why do we need to use synthetic compounds when giving female sex hormones
natural estradiol and progesterone have a large 1st pass effect orally (low bioavailability)
give examples of synthetic compounds of female sex hormones used
oestrogen = ethinyloestradiol (EE) progesterone = levonorgestrol, norethisterone
what are some of the main ways to classify female contraceptive choices
- hormonal/non hormonal
- routes
what are the most widely used form of temporary contraception and most efficacious
hormonal contraceptives
what are some of the routes of contraceptive
- oral
- injected
- implant
- intrauterine (emergency contraception)
what is often the first line hormonal contraceptive (if it can be prescribed)
combined oestrogen and progesterone
how can combined oestrogen and progesterone contraceptive be administered
- mostly combined oral contraceptive pill (COCP e.g. micogynon)
- patches
- vaginal rings
what is the traditional monthly dosage of COCP
21 days on, 7 days off ‘pill free interval’
what are some of the COCP ‘absolute’ contraindications
- migraine with aura
- heavy smoking AND >35yo
- breastfeeding <6 weeks post delivery
- uncontrolled hypertension (>160/100mmHg)
- personal history of VTE/cardio/cerebrovascular disease, current breast cancer
what is an example of progesterone only pill contraceptive
cerelle
how is the dosage POP different to COCP
take POP continuously w/o break
what other progesterone only contraceptive options are there
- injectable e.g. Depo Provera
- long acting reversible contraception (LARC); either implants e.g. nexplanon or intrauterine systems e.g. mirena coil
what is a key side effect of progesterone only contraceptive
irregular bleeding/spotting esp at initiation
what is the difference between copper coil and mirena coil
- both intrauterine systems
- copper is not hormonal
- mirena is hormonal
what is an example of emergency contraception
- ‘morning after pill’ levonelle or EllaOne (0-120hrs depending)
- copper coil (0-120hrs)
what should you consider when giving emergency contraception
- risk of STIs
- ongoing contraception
what considerations should be made during prescribing decision making
px characteristics:
- PMH
- organ function on other drugs
- allergies
- Px choice
risk: benefit ratio
- general risks and benefits for treating/not treating
- risks of given drug specifically for given Px
cost
- careful holistic costing specifically for Px and situation
evidence and guidance
