29F how to not abuse xanax? I'm currently withdrawing off of Effexor and my anxiety is off the charts. I have prescribed .5 mgs of xanax. I keep overthinking when I should take it because I don't want to abuse it/use it too often. Last thing I want is to withdraw from another drug. 

What's the safe way to use the xanax, as needed, without abusing it?? How do I know my anxiety is "serious enough" to take a xanax?