When your baby is half a month old, you can take cod liver oil as prescribed by your doctor. The timing of adding cod liver oil may vary due to the different conditions of babies. Usually, you can consider adding cod liver oil after a newborn is born for half a month. In the case of premature babies or twins, you can consider adding cod liver oil after two weeks or at other times, depending on the situation. Parents need to be aware that they need to consult a pediatrician to determine if their baby needs cod liver oil, when to add it, and how much to add, and to do so under the guidance of a doctor, and it is not recommended to add cod liver oil to a baby without permission. After adding cod liver oil, parents need to closely observe their baby’s stools. If the number of stools increases significantly, accompanied by crying and vomiting, the baby needs to go to the pediatrician in a timely manner so that the doctor can determine the specific situation and give effective treatment.