Zoloft (sertraline) works quite well for me (0 side effects). how likely is it for someone like me to develop a tolerance to zoloft (sertraline) if i keep using it for years?

There are some: People who find that after taking zoloft (sertraline) for a long period that it may lose some effectiveness. However, most folks who respond well to it can continue to use it long term without efficacy problems.

Possible: Young male healthy on a low dose of zoloft (sertraline) may need a higher level to reach effective state.

Very low: You don't develop tolerance to ssri's like zoloft (sertraline). That is one reason it works so well.