Hi, I had a gastric sleeve done last July and I have been experiencing symptoms such as shallow breathing, rapid pulse, dizziness, constant diarrohea and really itchy skin on my face and decolletage. I had initially put it down to being lactose intolerant, but just had a thought that I would research vitamin b12 deficiency, because I haven't been taking a multivitamin at all. I am thinking that this is what it may be. Rather than going and buying skin products it could be as easy as a Berocca daily. The dose of b12 in a Berocca is 10 mcg.