Omeprazole is used to treat ulcers and acid reflux, so why this was prescribed is a mystery as it will not do your wrist any good. Did your doctor xray your wrist to determine what is causing the pain? He shouldn't treat you with anything until he knows what he is treating. Contact your doctor for an explanation, something's not right with this. Good luck and take care!
Welcome to the gastroenterology community! That is a very very strange treatment for wrist joint pain and I have never heard of it used that way before. I would recommend calling your doctor and asking about this.