Posted by Elizabeth on July 4, 2001, at 21:57:10
In reply to Re: why do antidepressants work? » Edward, posted by blackjack on July 4, 2001, at 14:50:31
> That is not true of all drugs. Some drugs (marijuana comes to mind) actually produce a REVERSE tolerence, so the more you do it, the LESS you need to achieve the effect.
"Sensitisation."
> Also, since many drugs affect several different systems, they sometimes create a tolerence to some of their effects, but not others. Most people will develop a tolerence to the euphoric effects of amphetamines, and to many of the peripheral side effects, like sweating and increased blood pressure, but the focus, enhancing and sleep-redcing effects are often sustained at the same dose for a person's entire lifetime.
People who take amphetamine for fatigue do sometimes develop tolerance (as do those who take it for appetite reduction). It's not so much a sleep-reducer as a REM sleep-reducer, and that effect persists (e.g., in narcolepsy). People with ADHD are often able to stay on the same dose for years, though.
> It is thought, in the case of many antidepressants, that it is this very adjustment, not the immediate effects of the drugs, that is responsible for the sustained antidepressant effect.
It clearly isn't the immediate effects, since they generally take several weeks to work. < g >
> Some people do develop a tolerence to some antidepressants, however. I began to develop withdrawal symptoms while still taking more than the maximum recommended dosage of the MAOI Parnate, and my depression returned.
I had a similar thing happen on Nardil, but I also began experiencing withdrawal symptoms -- mood swings, panic attacks, REM rebound. Increasing the dose didn't work for me either. I tried going off the Nardil for a few months; when I tried taking it again, the same thing happened. (This isn't "tolerance" as it's generally understood, although it has sometimes been described as tolerance.)
Sometimes people experience a sort of contentment bordering on apathy after taking SSRIs for a long time. This isn't poop-out, but an unwanted side effect.
-elizabeth
poster:Elizabeth
thread:68829
URL: http://www.dr-bob.org/babble/20010701/msgs/69002.html