My legs and feet swell often. It is pitting edema. Especially after drinking alcohol. My liver enzymes, bun/creatine, echo normal. What could it be?

Alcohol. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, low fat milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco or alcohol in any form. Practice safe sex.
ADH (vasopressin) hormone. Alcohol, especially in women, has the ability to cause swelling of the hands and feet. This has to do with its effect on a hormone in the blood stream. Having said that, there are many other causes for swelling. The concern is the long term effects of alcohol on the both the liver and the kidney.