How is morphine used now and in the 1930s?

Several reasons.: Morphine is used for pain (acute and chronic) and shortness of breath. It has always been used for pain, earlier on it was for sleep, and during the last decades it was considered a must give for chest pain patients. That has since changed. . Some people use it for entertainment purposes, but that is not the purpose as prescribed by a physician or legally prescribed in the United States.