Yesterday was my first day of 25MG- half a pill twice a day. Today is day 2. I feel that I have built tolerance to my klonopin (which sucks and I had a feeling this would happen!) Once I took my second dose of Effexor, I was fine until the Klonopin wore off. At that point, I went to bed super late and all I could focus on was my heart thumping loudly. At that point, I got skipped beats- tried not to focus too much on it. That failed, so I took another klonopin to go to sleep, and here I am today dealing with the anxiety feeling. It had definitely increased with the Effexor. How long do I give this med to see if it works?