PART
2 - UNPLEASANT SIDE EFFECTS OF HRT
Side effects …
Why they occur and strategies to avoid them.
Most unpleasant
side effects of HRT, are related to (1) the oral route of administration,
(2) progesterone and progestins and (3) the physiologic action of the
hormone on its target tissue.
Side Effects
Related To The Oral Route Of Administration:
The most frequent
unpleasant hrt side effects associated with the oral route of administration
are nausea, vomiting and loss of appetite. These hrt symptoms can be
due to either a direct effect of the hormone replacement on the lining
of the stomach, or secondary to the affect of the rapidly rising hormone
levels on the brain. In the latter case this is not unlike “morning
sickness.” If the symptoms do not resolve after a few weeks a
reduction in dose, or switching to another oral product may be in order.
If this does not alleviate the symptoms a change to a non-oral route
of administration will be likely be required.
When a hormone is
taken orally it is absorbed by the gastrointestinal tract and transported
“en masse,” or as a “bolus” to the liver. This
is referred to as the “first-pass” affect. During this passage
the absorbed hormone alters the normal production of liver proteins.
While most women seem to be unaffected in some women the alteration
in the blood levels of these substances have the potential to cause
an elevation of blood pressure and/or an increase in the frequency of
migraine headaches.
Side Effects
Unrelated To The Oral Route Of Administration:
One problem that
is not specific to the oral route and can occur with any route of administration
is breast tenderness. It can be perfectly normal for a woman who has
been hormonally deficient to have breast soreness beginning a few weeks
after starting estrogen replacement. Low estrogen levels can result
in an involution of breast tissue and when the breast tissue is stimulated
by estrogen replacement the breast tissue can be sore and tender for
2-3 months as the breast tissue regenerates. Women who have been estrogen
deficient may notice a reduction in breast size and then notice a return
to their pre-deficient state after taking replacement estrogen. If a
woman does not recognize the reason for the breast soreness, she may
suspect the discomfort has a more serious origin, become frightened
and stop her HRT. If the tenderness persists for more than 2-3 months,
a reduction in dose may be required. Of course it would be prudent for
her to discuss this with her physician and have an examination if it
persists, or if the physician believes it is warranted.
It is also possible
to experience allergic reactions to HRT preparations. Women who are
allergic to peanuts need to be aware that some hormone replacement preparations
including Prometrium contain peanut oil and are capable of producing
serious allergic reactions in those who are susceptible. Many women
are allergic to the adhesive in transdermal estradiol patches, or find
that they are intolerant to the vehicle in the patch resevoir that contains
the medication. In some instances this can be resolved by using another
brand of transdermal estrogen patch.
One frequent reason
given by women for not starting HRT, or discontinuing its use is the
prospect of continued uterine bleeding. A woman who has an intact uterus
and is an estrogen user requires the use of a natural, or synthetic
progestin to prevent potential overstimulation and the development of
abnormal changes of the uterine lining. Women who are on a program of
sequential therapy in which the progestin is give for 10-12 days a month
will experience an expected withdrawal bleeding. HRT preparations are
available that contain a combination of estrogen and a smaller dose
of progestin which have been designed to be taken daily and prevent
any uterine bleeding. These preparations are widely used and are preferred
by many physicians, but others have a concern about the affects of daily
use of progestins. Most women tolerate this combination well, but others
are intolerant to daily use of even a small dose of progestin and/or
find that they continue to experience spotting, bleeding, or cramping
while using it. The subject of progestin and progesterone intolerance
will be addressed
further in the next section.
Many women are concerned
that weight gain may occur if they use HRT. The research evidence does
not support this and suggests that women who are users of HRT are actually
less likely than non-users to put on extra pounds. This is discussed
in the section of the web page, Menopause & Weight Gain.
PART
1 - FINDING AN IDEAL REGIMEN... How does a woman find an HRT program
that relieves her symptoms and doesn’t cause side effects?
PART
2 - UNPLEASANT SIDE EFFECTS OF HRT… Why they occur and strategies
to avoid them.
PART
3 -PROGESTERONE, PROGESTINS & PROGESTERONE CREAM...What exactly
are progesterone and progestins?