The seeds contain 50% oil. In the oil there are established fatty acids such as ricinoleic (90%), linoleic, oleic, linolenic and palmitic.In the seeds there is ricin, a substance that can cause a very serious poisoning.Castor oil is orally used as a laxative and topically as an anti-inflammatory medicine on the skin. It appears as excipient in several dermatological and cosmetic preparations. At latest update relevant published data on excretion into breast milk were not found. The ricinoleic acid is an irritant of the intestinal mucosa where it is readily absorbed, being able to appear in the milk. It is highly recommended to use a safer laxative while breastfeeding. Castor oil, either orally (Winterfeld 2012) or topically applied on the breast (Rasiya 2011), has been used as a galactogogue without any proof on effectiveness. On the other hand, it has also been allegedly used to reduce milk production (Hardy 2000, Eglash 2014 ).The best galactogogue-like results are attained through a frequent and on demand breastfeeding along with a correct technique (ABM 2011). In some cultures castor oil is administered instead of colostrum to infants in the first few days of life (Benakappa 1989), being this a risky practice, since diarrhea, dehydration, insomnia and tremor can occur. Topical use on the skin is not contraindicated during lactation, provided it is not applied on the breast and areas where the infant can touch and absorb it are avoided.