Hi Dear, Welcome to HCM. Understanding your concern. As per your query your daughter have symptoms of fever and canker sores in mouth after drinking alcohol is not because of herpes rather it is because of the fact that they are auto-immune, which means that your body is essentially attacking itself. Alcohol can lead to folic acid deficiency, which in turn can trigger canker sores. Folic acid, or folate, is a type of B vitamin that helps in the DNA repair process. By interfering with folic acid absorption and increasing folate excretion through urine, excessive alcohol intake may result in a mouthful of burdensome canker sores. Alcohol s ability to dry out the mouth, leaving it more vulnerable to these little infections. I would suggest you not to panic about it. Drink plenty of water before going to sleep. Hydrating your body works to combat the effects of alcohol, replenishing cells and keeping the mouth moist during sleep. Eat foods high in folic acid. Some breakfast cereals have an enriched source of folic acid. Leafy vegetables and legumes may be another good bet. Consider eating these foods before drinking. Hope your concern has been resolved. Get Well Soon. Best Wishes, Dr. Harry Maheshwari