Why did my PremPro stop working after 7 yrs?

Dear Doctor,
I am a 64 yr. old POST-menopausal woman who has been taking PremPro at 0.625/.5 for 7 years (2000-Dec 2007)
All of a sudden it just stopped working and I had anxiety, depression, and could not sleep.  Why would this happen?
I love PremPro and it was the only HRT that made me feel wonderful !!!   Six months ago after this happened the doctor put me on 30mgs. of Paxil and 2 mgs. of Xanax ( which is rather high amount).......I then went to a holistic doctor who wants me off the Paxil and the Xanax and has now put me on bioidentical hormone creme (biest 1.25, progesterone, 2mg. and testosterone at 2 mg.  I do not feel as bright and alert on the compounded or bioidentical hormones as I did on the PremPro.......do you think I should try going back on the PremPro or perhaps FEMHRT as I seem to get better and faster results on synthetic hormones.  I had heard that once the receptors in the brain get used to synthetic hormones like PremPro, it is harder to get them to recognize any other kind of natural hormone....

[Machelle Seibel, MD]

There is no question that what works best for one person might not work best for the next. However, why PremPro suddenly stopped working is unclear. Other medications could interfere. A certain batch of pills might not be produced with the stated amount of hormone in them. It is reasonable to try the prempro again. However, I am unaware of any information that suggests brain receptors can only get used to one type of estrogen.
I would agree with your holistic doctor that if you can get the estrogen dosing correct, there is a good chance you will not need the other medications.
Machelle M. Seibel, MD