Research has repeatedly indicated that analgesics such as morphine have a higher incidence in men than in women. According to a study conducted at Georgia State University in Atlanta with rats, this is because males have more receptors for these drugs in a portion of the brain that processes pain. Male and female rats also have a different sensitivity to morphine, so they have been analyzed with these animals. They know that the difference observed in rats does not have to appear in humans, but researchers believe that this experiment has shown that the sexes should separately analyze pain medications.