In such cases, drugs such as naloxone and naltrexone provide molecules that bind to opioidreceptors with a higher affinity than the opioids themselves, but do not activate the receptors.
One of the most cited studies, by University of Washington researcher Adam Drewnowski, found that women who were given a drug that blocks opioidreceptors consumed less sweet, high-fat foods--but only if they were bulimic.