Well, generally speaking, it is normal to have I do not think the nausea can be caused by the prk surgery. Nausea is the sensation of unease and discomfort in the upper stomach and head with an urge to vomit. So we can say that it is a kind of problem which is about the stomach. Generally speaking, alcohol, or stress are the causes which can lead to it. And it is common to occur from a viral infection, food poisoning, milk allergy, motion sickness, overeating or feeding, coughing, or blocked intestines and high fever. But there is nothing to do with prk surgery. There are many tips you should pay attention to, if you have taken the surgery. For example, you should be careful when you have shower. For foods, you should eat foods high in beta-carotene, Vitamin C and Vitamin E.