Ronnie -- It is the nature of clinical research. Even with our exhaustive drug approval process in the US - these drugs are generally still only being tested on a group of individuals in a controlled situation by physicians who are very familiar with the NDE (new drug entity)...and for a decidedly limited time (which varies by indication).

Side effects start to show themselves in aftermarket studies (phase 4 clinical trials) which are longer in duration....but then datapoints and trends show up once any physician can write a scrip for the drug....the drugs are taken by a wider variety of people in terms of age, health, gender, racial, ethnic factors and lifestyle differences. It can take a number of years before there's enough data (assuming it's reported back to the FDA or the drug company) indicating that there may be a problem.....and then if the problem is considered significant - there is a process to put warnings on the labeling for these drugs....but then that requires more testing.

In general, withdrawal from SSRIs/SNRIs by individuals without any significant comorbidities is safe - even if someone decides to go cold turkey (which isn't saying it's a good idea) -- but withdrawal can be unpleasant. Getting on these drugs can be pretty damn unpleasant as well....but that is a factor with many drugs.