Route of administration
The medications used in menopausal HRT are available in numerous different formulations for use by a variety of different routes of administration:
Oral administration – tablets, capsules
Transdermal administration – patches, gels, creams
Vaginal administration – tablets, creams, suppositories, rings
Intramuscular or subcutaneous injection – solutions in vials or ampoules
Subcutaneous implant – surgically-inserted pellets placed into fat tissue
Less commonly sublingual, buccal, intranasal, and rectal administration, as well as intrauterine devicesMore recently developed forms of drug delivery are alleged to have increased local effect lower dosing, fewer side effects, and constant rather than cyclical serum hormone levels. Transdermal and vaginal estrogen, in particular, avoid first pass metabolism through the liver. This in turn prevents an increase in clotting factors and accumulation of anti-estrogenic metabolites, resulting in fewer adverse side effects, particularly with regard to cardiovascular disease and stroke.Injectable forms of estradiol are no longer recommended in menopausal hormone therapy due to the availability of other formulations. Bioidentical hormone therapy
Bioidentical hormone therapy (BHT) is the usage of hormones that are chemically identical to those produced in the body. Although proponents of BHT claim advantages over non-bioidentical or conventional hormone therapy, the FDA does not recognize the term bioidentical hormone, stating there is no scientific evidence that these hormones are identical to their naturally occurring counterparts. There are, however, FDA approved products containing hormones classified as bioidentical.Bioidentical hormones can be used in either pharmaceutical or compounded preparations, with the latter generally not recommended by regulatory bodies due to their lack of standardization and regulatory oversight.
Potential menopausal symptoms include:
Hot flashes – vasomotor symptoms
Vulvovaginal atrophy – atrophic vaginitis and dryness
Dyspareunia – painful sexual intercourse due to vaginal atrophy and lack of lubrication
Bone loss – decreased bone mineral density, which can eventually lead to osteopenia, osteoporosis, and associated fractures
Decreased sexual desire
Defeminization – diminished feminine fat distribution and accelerated skin aging
Sleep disturbances and joint painThe most common of these are loss of sexual drive and vaginal dryness. Heart disease
The effect of HRT in menopause appears to be divergent, with lower risk of heart disease when started within five years, but no impact after ten. There may be an increase in heart disease if HRT is given twenty years post-menopause. This variability has led some reviews to suggest an absence of significant effect on morbidity. Importantly, there is no difference in long-term mortality from HRT, regardless of age.A Cochrane review suggested that women starting HRT less than 10 years after menopause had lower mortality and coronary heart disease, without any strong effect on the risk of stroke and pulmonary embolism. Those starting therapy more than 10 years after menopause showed little effect on mortality and coronary heart disease, but an increased risk of stroke. Both therapies had an association with venous clots and pulmonary embolism.HRT with estrogen and progesterone also improves cholesterol levels. With menopause, HDL decreases, while LDL, triglycerides and lipoprotein a increase, patterns that reverse with estrogen. Beyond this, HRT improves heart contraction, coronary blood flow, sugar metabolism, and decreases platelet aggregation and plaque formation.