Adults taking Imodium AD caplets should take two caplets after the first loose stool, followed by one caplet after each additional loose stool, but they should not take more than four caplets in 24 hours. Each caplet contains 2 milligrams of loperamide HCl, according to Imodium.com.
Imodium AD is also available in liquid form, for which the adult dosing is 30 milliliters, or 6 teaspoons, after the first loose stool, followed by 15 milliliters, or 3 teaspoons, after each additional loose stool. Adults taking the liquid form should not take more than 60 milliliters, or 12 teaspoons, in 24 hours, warns Imodium.com. If symptoms do not improve after two days (or 10 days, for chronic diarrhea), if a fever develops, or if stools appear bloody or black, medical attention is necessary, notes MedlinePlus.