I,ve been on effexor for 2 years. I started out the first week with 37.5 mg then increased after 1 week to 75 mg. Don't stop taking it. I stopped after one year thinking I was cured because I had not experienced an attack in over 6 months. BIG MISTAKE!!!! I now get panic attacks about 5 days a week and had to increase my dose to 112.5 mg. I've been back on my meds for 7 months. Insomnia is a bad side effect. It takes about 8 weeks to kick in. just keep on it.