Hi Emmy and welcome!
I am sorry to hear of your recent trouble with your Rx. We have had many posts on the subject of A/D meds and weight gain, so know that you are not alone.
Using and A/D off label for menopausal symptoms was a new one for me...so I did a little reading, and here are some ideas that I can recommend asking your prescrbing doctor about
:
*Since the Effexor is causing unwanted weight gain, can you possibly try another SNRI? Pristiq is a newer Rx, that has been approved specifically for treatment of menopause symptoms
*Is is possible to try an SSRI instead? This class of drug differs from Effexor and Pristiq in it's make up, but treats similar issues...perhaps without the weight gain side effect for you?
I wish I could be of more help. Keep checking back and perhaps you will get a response from someone with more experience in this subject. Here is a link on Pristiq that you may also find informative:
http://www.crazymeds.us/pmwiki/pmwiki.php/Meds/Pristiq
Wishing you the best...and post with us anytime.;)
Scaredy Cat