My brother asked me which brand of lactase pills do I use? Background: my family are all lactose intolerant. I call it one of the Kao family CURSES. It's gotten very bad for me. Many foods that I formerly ate are now completely off limits if I don't want to spend 45 minutes in the bathroom having cramping, gas and diarrhea. Where it hits me hardest is not being able to eat Giordano's stuffed cheese and sausage pizza or Giordano's stuffed spinach pizza. For people not familiar with Chicago deep dish pizza, let me tell you, there's no better pizza in the world. Sorry to the Lou Malnati's, Pizzeria Uno's, Gino's East fans. It's also very annoying around birthdays and at Christmas time. I have literally had to sit through our own office's Christmas party for several years consecutively because the preordered menu went something like this: hors dourves brie cheese or onion dip, lobster bisque soup, salad with goat cheese, steak with whipped cream on potatoes and fettucine alfredo, and a giant slice of cheese cake to top things off. I was pretty hungry by the end of that night. But I digress.
There is no brand that is superior to any other based on studies. So I use whatever is the cheapest, while keeping my eye on the number of FCC units per pill. The WHAT?! FCC units are best defined as "a U.S. measure of purity and effectiveness for chemical substances added to foods. FCC stands for Food Chemical Codex, a code of standards prepared by the U.S. Institute of Medicine for the U.S. Food and Drug Administration. Perhaps most familiar to consumers is the FCC unit for the enzyme lactase, taken by those who are lactose intolerant. There is no definite conversion between FCC units and milligrams, because different manufacturers prepare their products in different ways. Instead, FCC units provide a way to judge the relative effectiveness of different preparations, no matter what their weights." ( Source )
The number of FCC units you should take varies with directly with the degree of your lactose intolerance and the amount of lactose you are eating. Figure in some foods are very rich in lactose per each bite. I have found them to be helpful, but since I am usually not at home when potentially eating lactose-containing foods, my usual plan is to avoid them.
If you also have the curse of severe lactose-intolerance and you don't want to completely avoid diary products, you might consider taking a replacement pill containing lactase. Discuss the pros and cons with your doctor.