Codeine 300/30mg is a prescription medication combining 300mg of acetaminophen and 30mg of codeine phosphate. It is used to manage moderate to moderately severe pain when non-opioid pain relievers are not sufficient. Codeine is an opioid that alters pain perception in the brain, while acetaminophen enhances its pain-relieving effects. This combination provides effective short-term relief after surgeries, injuries, or for certain medical conditions.