Think of your body as the inside of Wal-Mart and how you take the estrogen as the door. Where the drug goes into the body, the door, will be where you find the highest concentration. Just like if you walk into the Super Wal-Mart at 2am you will be most likely to find people if you look at the front door.
So, if your symptoms are vaginal dryness, you might take estrogen as a vaginal cream and allow total body blood levels to stay low while achieving very high levels where you want the effect of a healthy vaginal mucosa.
If your symptoms are urinary incontinence, then you may again use a vaginal cream around the urethra to help build the tissue (but using a cream there instead of just taking a pill allows high levels where you want the effect while keeping total body levels low).
If you are having hot flashes, you may avoid the liver (which changes the estradiol into estrone, perhaps one of the more dangerous of the estrogens) by taking your estrogen as either
If you are developing a dried, wrinkled face, then you may want a different facial cream.
If you have facial hair, again, you may want a different strength facial cream.
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