Need help - Withdrawal symptoms from ventab xl 150 mg (effexor).

Hello i am currently getting off ventab 150 mg. I was on it for 3 years. My psychiatrist has only reduced my dosage from 150 mg to 112.5 mg and bridging it with an SSRI (voxigain) 20 mg.
It's been a month since i am on 112.5mg but the withdrawal does not seem to get better. I can't sleep, i feel like i am in a forever panic state, anxiety is off the roof, really unbearable depression. The SSRI (voxiagian) has not kicked in yet or it is not working i don't know.
Please if someone has a had a similar experience please let me know how to help myself. Is it possible to get off this drug? Will I be okay?