Posted by Garnet71 on January 12, 2009, at 22:00:44
In reply to Antidepressant withdrawal syndrome, posted by Garnet71 on January 12, 2009, at 21:59:20
"What exactly is antidepressant withdrawal syndrome? is a question that comes up over and over on paxilprogress and, I imagine, similar boards all over the world. I've done 4 years of research on it, finally found a doctor who understands it, and, while I'm not a medical expert, I believe I can describe the ballpark.
The initial issue in antidepressant withdrawal syndrome is rebound of other systems (with Paxil, including the cholinergic) while the serotonin system is still downregulated. For some people, it takes a long time for the serotonin receptors to correct. In the meantime, other systems take over and establish a dysfunctional homeostasis without adequate serotonergic participation.
This dysfunctional homeostasis leaves some people, such as myself, with a hyper-reactive glutamatergic system. (This is part of the limbic system deep within the brain and the body-wide autonomic system.) Reacting with "fight or flight" to the least stimulation, the glutamatergic system signals the adrenals to create excessive cortisol. The cortisol level may be elevated enough to show up in conventional testing, but since it is not related to adrenal or pituitary tumor, medicine doesn't know what to do with that information.
Theories of serotonin or dopamine deficiency etc. are particularly stubborn red herrings. The mythology of neurotransmitter imbalance is not relevant in withdrawal. The issue has moved to the glutamatergic system, norepinephrine, noradrenaline, and cortisol. Interventions that reduce cortisol are helpful. Noradrenergic medications such as buproprion (Wellbutrin) and mirtazapine (Remeron) are not. Celexa and other SSRIs may be noradrenergically activating.
Spurts of elevated cortisol causes many symptoms, from muscle stiffness and pain to waves of anxiety and despair. CNS instability causes symptoms my doctor calls "autonomic dumping," with fast heartbeat and waves of othe unpleasant sensations. Excessive glutamatergic activity and inappropriately raised cortisol at night causes the awful withdrawal insomnia.
This is not a relapse or emergence of depression, etc. It is a neurological syndrome all on its own.
In chronic withdrawal insomnia like mine, because of damage from withdrawal, the alerting setpoint of the glutamatergic system has been set too low -- hyper-vigilance. My doctor calls this a meta-homeostasis. The brain wants to keep us alert to respond to (non-existent) threats, and wakes us up when we become too inattentive. Tragically, the alerting response is triggered by the relaxation of sleep. In sleep medicine terms, this is called alpha intrusion. It is not a circadian rhythm disorder.
To re-establish the brain's natural ability to sleep, the glutamatergic system has to be gradually tamed. Too strong an intervention, even deep sleep, will cause the meta-homeostasis to increase glutamatergic activity. This paradoxical aspect of the condition is particularly hard to understand.
I am being treated with very low-dose Lamictal (now 1.07mg) to reduce glutamatergic activity and, at night, 2mg of melatonin at 7pm and low-dose Lyrica at 9pm to induce sleep. It's taken 10 months but I now believe I am about 85% on the way to recovery. I am now sleeping at least 4 hours a night and haven't had a sleepless night in a month. (Since January, I have had at least one or two sleepless nights a week and maybe 3-4 hours of sleep the other nights.)
According to my doctor, the signal from endogenous melatonin recruits the brain's ancient sleep system, which eventually will overcome the hyper-vigilance of the disorder glutamatergic system. He says his gradual approach with very low doses of drugs is all they have for now.
I have had no problems with Lyrica and expect to be able to taper off without a problem.
When I am all done with this (cross fingers), I am going to stay far, far away from psychiatric drugs. I expect my nervous system would still be susceptible to damage from them. I suggest anyone who has experienced a bad drug withdrawal avoid any neurologically active drugs in the future if you are at all able to do so."
poster:Garnet71
thread:873588
URL: http://www.dr-bob.org/babble/20090104/msgs/873642.html