Given you have given little detail, as others have said, there is limited advice we can give, but given the anxiety problems, and I imagine there are other things too, to me there are two things you can do:
1) try to help him with the anxiety issues (and others if they exist), which may help; and I'm, inclined to say
2) if it persists, try to persuade him to seek professional help, the NHS is there to serve YOU and keep YOU healthy (not just the NHS, obviously there will be people at college/university or wherever)
Based on your last comment, and based on personal experience, does he drink much? And if so has it recently increased, because personally when I drink excessively my emotions, namely anger and depression, get a bit out of control. As for the upset bit, is the "that might cause upset to others" have the "others" as Male or Female, because you have to remember that males and females are pretty different emotionally.