Post-operative nausea or vomiting can be normal immediately after your bariatric surgery. You may be introducing new foods to your diet, and it takes time for your body to adjust to the reduction of calories. However, if you are not straying from your diet and exercise regimen and still feeling the effects of nausea, this can be a sign that you need revision surgery. Vomiting, a more serious symptom, can indicate a complication with your previous surgery. It is important to make your physician aware if your symptoms persist.