I hope you have discussed your withdrawal from Effexor with a decent physician and are stepping down your dosage over a period of weeks or more. If not, you may be experiencing a type of withdrawal rebound; it usually takes a little time for your nervous system adapt back to the non-medicated state.

Not sure if your doc has discussed this with you, but I will try to give a very brief lay-person run down for you... it has been a while for me. Neurotransmitters are chemicals that transfer a nerve signal from one nerve to another: from the synaptic end bulb (sender) - across the synaptic cleft - to receptors in the receiving nerve, which then triggers a response in the receiving nerve. The neurotransmitters are removed from the cleft by a range of mechanisms, one being uptake back into the end bulb of the sending nerve. Effexor inhibits this uptake, thereby (at least in the short term) increasing the amount of transmitter in the cleft and increasing the transmitters available to bind receptors in the receiving nerve. This causes increased stimulation of the receiving nerve, compared to a non-medicated state. There is MUCH more to this, but I am trying to keep it simple (makes it easier for me!) and I don’t have my reference texts close by!

Thing is, your synapses have regulated themselves to manage the increased serotonin and noradrenaline at their gap and may take a little time to regulate back to the lower amounts of these transmitters in the gap. That is, your nerves have gotten used to having higher levels of neurotransmitter available; now they need to get used to more 'normal' amounts. It takes time. Hang in there. Find an understanding and helpful doc.

Hope this helps in some small way. It shouldn't - your doc should have explained it to you already, tho likely did not.

Cheers
Raymond