Do antidepressants slow aging

Not directly. In an environment in which psychosomatic disorders are a cause of physical stress, then antidepressants could help indirectly to avoid the acceleration of aging caused by such stress

Good answer. I should add that in my own experience and observation among several friends, family and co-workers, those few that have been on antidepressants for many years seem visibly 'younger' than those not. I think this may be an effect that being on these medications may reduce overall stress over the long term and thus reduce stress-related aging such as some wrinkling and hair loss. It's just my observation and experience of course but there does seem to be something to it.