I've seen many medical doctors in my time. And I've noticed that none of them would tell me what the potential side effects of a medication they had just prescribed me could be unless I asked them.
But I worked with one psychiatrist who, even when I asked him about it when he'd prescribe me medication, wouldn't tell me what the potential side effects were.
It's impossible for any psychiatrist to be able to remember every possible side effect to every single psychiatric medication. It's too much for even the best psychiatrists to remember. However, this doctor wouldn't tell me anything.
If you're prescribed a medication by a psychiatrist and you want to know what the side effects might be, you have the right to know. If you ask this and don't get enough information about the new medication, put your foot down. This is your mental and physical health we're talking about, after all.