It is difficult to avoid the use of all prescription drugs while breastfeeding – especially if you are having multiple children and nursing for a length of time with each one. And then there are the street drugs that nobody speaks of. If you are in the habit of using these when you become pregnant, you may need assistance and some honest research to prove how harmful they can be. As with any medical questions in pregnancy and during breastfeeding, your doctor or midwife will know more about your personal history and circumstances than any website, but it is always good to gain as much knowledge as possible in order make the ultimate decision about the health of your baby.