When a nursing mother takes in a drug or a food, a small part of it goes into her milk. If you are at home after early discharge from the hospital, do not take any medication without first checking with your doctor or midwife. Almost all medication appears in only small amounts in human milk. Very few prescription medications can not be prescribed for breastfeeding women. The American Academy of Pediatrics published a list of drugs that nursing mothers should not use .
All street drugs are dangerous to the nursing baby.
Alcohol goes into a mother's milk very quickly. It is not safe for a nursing mother to breastfeed her baby the morning after she has drunk alcohol. Caffeine does not seem to bother most nursing babies if the mother takes in less than 2 cups of coffee or 2 Cokes a day. Larger amounts may make your baby wakeful and crabby. Some nursing mothers who smoke cigarettes have a decreased milk supply.