Hi, KelBel.  I wonder, if you call now, if you could get your son into a mental health clinic for an appointment with a psychologist, who would be able to do an assessment and even figure out if medication would help.  Do you think he would be willing to go?  The other thing he could do is go to the student health services at his college, I think they're quite used to dealing with students with depression.   No, I don't think 18 is too young to take antidepressants.  Both of my sons have been on them since long before that.  I know they say that teens and young adults have a greater risk of getting more depressed or suicidal ideation on some of them, but I don't know if that risk is worse than the risk of getting more depressed and suicidal by NOT taking them.   I hope you can help him find a solution; it might make more sense for him to get help where he's going to school, since he's there most of the time.  It's good that you're recognizing the symptoms.  Let us know how it works out.