Is it harmful to stay on Zoloft for many years?
Not really. The problem with SSRIs is not that it is bad to stay on them, but they do tend to lose their effectiveness. This is because they do nothing for the production of serotonin. They are selective serotonin reuptake inhibitors, and what they do is make it such that the cells do not reabsorb the serotonin as rapidly as they should, thereby increasing the effect of serotonin levels, in what is called the neural cleft. Wonderful, but unless you do something to increase the production of serotonin, the body adapts to it.
Generally, what i do, is start people on something called 5-hydroxytryptophan, or 5-HTP. That increases the cells’ production of serotonin, and makes the SSRIs more effective.
You have to be careful, though. if your body had adapted to the SRIs in the absence of the 5-HTP, it is easy to overdo it. We start people off at low doses, and increase gradually if need be. Longer use of Zoloft is not harmful; as long as you are taking the 5-HTP, the SSRIs will work fine.