There are many ways of treating depression, one of which is administering antidepressants. From this site, and several others, I read that risk of suicide increases after starting an antidepressant.
A few people do become more agitated, depressed, and anxious shortly after an antidepressant is started or after the dose is increased. Some people, especially younger children and adolescents, become increasingly suicidal if these symptoms are not detected and rapidly treated. This finding was first reported with SSRIs, but the risk probably does not differ among classes of antidepressants.
My question is, simply, why is that? These antidepressants work long-term, but cause strong suicidal thoughts when taken initially. Does it have something to do with hormones?