This
page discusses methods of hormone replacement therapy - hrt - and includes
discussions of routes of administration ie; oral, transdermal patches
and gels, subcutaneous implants, creams, injections, suppositories and
discusses estrogen, progesterone and testosterone.
There is no perfect
method of HRT and none precisely mimics nature. Fortunately this isn't
all bad. During a woman's reproductive years, peaks and valleys of hormone
concentration in the blood are necessary to trigger ovulation and if
conception does not occur, menstruation. These swings in hormone levels
can effect mood and sense of well being. For example many women experience
a sense of euphoria during pregnancy when their levels of sex hormones
are very high and PMS is related to the decline in hormone levels prior
to menstruation.
It is of note that
some patients request that they be given the "lowest possible dose"
of HRT a reflection of a perception that somehow HRT is unwise, dangerous,
unnatural or all of the above. This is contradicted by the weight of
medical research which suggests HRT increases longevity and enhances
quality of life. Ideally, HRT should be given in a dose appropriate
for each specific individual as everyone differs in their needs and
capacity to absorb and metabolize hormones. Ideally, this would be in
an amount sufficient to fully accomplish its beneficial effect.
The hormones
replaced in menopausal women include:
Estrogen
The ovarian hormone responsible for the development and maintenance
of what we refer to as secondary sexual characteristics.
Progesterone
The ovarian hormone responsible for protecting the uterine lining from
being overly stimulated by estrogen. Estrogen given alone (unopposed)
when the uterus is present can result in the development of abnormal
changes of the endometrium (uterine lining) including cancer. The addition
of adequate amounts of progesterone to a program of HRT prevents this
from occurring. Progesterone is not usually given following a hysterectomy
as there is no uterine lining present to protect. Unfortunately, although
necessary progesterone causes "PMS" like symptoms in approximately
30-40% of patients. This is mild in the majority of patients but can
be severe in a small percentage.
Testosterone
The ovarian hormone responsible for sex drive, energy, muscle mass and
assertiveness. Thought by many to be exclusively a male hormone it has
important functions in women. Along with the other ovarian hormones
it is markedly diminished following ovarian removal or injury and consideration
should be given to appropriate replacement.
Any of these sex
hormones, estrogen, testosterone and progesterone can be administered
alone or in combination.
In addition there
are a number of routes of administration available to get these hormones
into your system. They include:
•Oral
•Transdermal
Patch
•Transdermal
Gel
•Sublingual
•Injections
•Creams
•Suppositories
•Subcutaneous
implants
There is no "best" method for everybody and your choice may
be influenced by:
•Type of menopause
•Concurrent medical conditions
•Age at menopause
•Response to previous therapy
•Current age
•Intolerance to previous HRT program
•Symptoms
•Individual perception of HRT program
•Hormones to be replaced
•Individual psychological makeup
Ultimately, the
choice of which hormone or hormones and which route of administration
should depend on what each individual is comfortable with in view of
what she perceives to be her needs, goals and lifestyle.
Estrogen, progesterone
and testosterone can all be given using any of the described methods.
But, for the sake of clarity and simplicity and to lessen confusion
(mine, because I can't figure out how to do it all at once) I will first
discuss the routes of administration using estrogen alone. I will then
go on to progesterone, testosterone, combination therapy, indications
for each and rationales.
Estrogen
Therapy
The oral route of HRT, usually a tablet taken daily is the most frequently
utilized method of HRT in the world. The most well known oral estrogen
replacement product is sold under the brand name Premarin and is a "conjugated
equine estrogen" and is extracted from pregnant mare's urine. There
are several other oral estrogen products available and each manufacturer
gives various reasons why their product is superior. I prefer to use
brand name over generic products when possible because I believe some
generic formulations of estrogen are not bioequivelent. The advantages
of the oral route include that for most people it's easy to take a pill,
it's relatively inexpensive and for most women it effectively delivers
estrogen into the bloodstream. There are some disadvantages. It is not
effective in everyone and causes nausea or other gastrointestinal upsets
and occasionally headaches. Infrequently it may cause an elevation in
blood pressure. Some of these problems may be related to what is termed
the bolus effect on the liver. After an estrogen tablet is absorbed
by the upper gastrointestinal tract it is transported directly to the
liver. This supraphysiologic amount of estrogen arriving all at once
induces the the cells of the liver to alter its production of enzymes.
Transdermal
Patch methods for estrogen administration has the hypothetical
advantage of avoiding this "first liver pass" and at times
can be effective in patients who don't respond to tablets. There are
a number of patches available today and they share some common elements.
Estradiol the bioactive estrogen, a delivery system which allows the
hormone to be gradually absorbed by the skin and an adhesive to keep
it on. It is applied to the skin and replaced once or twice weekly as
contrasted to the daily estrogen tablet. The estrogen is absorbed gradually
over the length of time each individual patch is worn and this is more
physiologic. It has the disadvantage of causing skin irritation in 10-30%
of those who try it. Sometimes this is mild and can be alleviated simply
by moving the patch to a different area of skin daily but can be severe
enough to require its discontinuance. It is not as acceptable to some
women who exercise strenuously or live in warmer climates as there is
greater difficulty with adherence to the skin with increased perspiration.
When skin irritation is the caused by the adhesive in the patch delivery
system estrogen gel is available from a number of pharmacies and can
be rubbed directly on the skin daily without the use of the patch system
and is an effective alternative.
Transdermal
Gel is a very useful method of estrogen replacement. A measured
amount of gel is rubbed on the skin once daily. It is absorbed and in
theory at least, the skin acting as a reservoir releases it gradually
into the bloodstream. It is simple, well tolerated, relatively inexpensive,
there is no "bolus" effect and it avoids the "first liver
pass". It is basically the patch minus the adhesive and "delivery
system". Pretty nifty, eh! And of course is not widely available
in this country.
Sublingual
administration of estrogen can be used and in this method a
tablet, usually "estradiol" the bioactive form of estrogen
is placed under the tongue. It is absorbed through the lining of the
mouth into the blood vessels located under the tongue and then into
the bloodstream. It avoids the "first liver pass" but is delivered
into the blood all at one time as opposed to the gradual "trickle"
delivery of the patch.
Intramuscular
Injection is a common method of estrogen replacement and is
used by many physicians. The hormone is usually mixed with a substance
to slow its release into the bloodstream and depending on the dose and
patient response is usually given at 2-4 week intervals. It has the
disadvantage of relatively high levels soon after administration which
decline rapidly after a week or so. Unfortunately, this may perpetuate
menopausal symptoms which are often associated with declining rather
than absolute hormone levels.
Creams
have been used as a method of HR. for several years and is an interesting
story. Vaginal dryness and loss of elasticity of the "vaginal barrel"
can be a distressing symptom of hormone deficiency. Estrogen cream was
considered a " local" nonsystemic therapy and was an effective
treatment for this problem. Years ago (and I'm sure today) it was prescribed
in those instances when the doctor (presumably not knowledgeable about
HRT) or the patient or both were not comfortable using other methods.
The rational being that since it was local therapy it wouldn't pose
any of the "dreaded risks" of systemic HRT. Incredibly, most
doctors and patients were not aware that the vaginal absorption of estrogen
is much more efficient and in the doses prescribed results in significantly
higher blood levels of hormone than the oral or transdermal route of
administration. Wait! It gets better! Some women found it convenient
to regularly use the cream as a lubricant to facilitate intercourse.
After all they put in in at night anyway. Well folks, the skin of the
penis absorbs estrogen pretty well too. Not as efficiently as the vagina,
but well enough to result in feminizing changes and impotence in the
partners of these women.
Suppositories
perform the same function as the cream delivery method. They are preferred
by some users who find them less messy.
Subcutaneous
Implantation of estrogen pellets is a method used primarily
by physicians who special interest or training in the treatment of menopausal
women. It is an effective treatment for menopausal symptoms which have
been unresponsive to other therapies. I have found it to be the therapy
of choice when other methods of HRT have failed as is too often the
case following hysterectomy and ovarian removal. It can restore quality
of life when the problem is diminished interest in sex, insomnia or
persistent hot flashes. The pellets which consist of estradiol, are
derived from Soy a naturally occurring substance. They are inserted
into the subcutaneous tissue of the abdomen or buttock usually at 3-6
month intervals.