Familial Mediteranean Fever is a disease that is transmitted in an autosomal recessive fashion. It consists of bouts of fever, joint pain and abdominal and sometimes chest pain. The bouts are generally self limited but painful. Cholchicine has been shown to diminish the frequency of attacks. The reason you see little of it in the literature is that it is rather infrequent in the US (It is barely mentioned in Nelson Textbook of Pediatrics. Rudolph's textbook has more information.) It is rather common here in Israel as it is most likely in those of Mediterranean extraction such as North Africa. Plain and simple, the AAP considers it compatible with breastfeeding thus I see no reason why your client should be concerned. It is used in young children with FMF also. According to the references in Briggs, Friedman and Yaffee there seems to more concern about using it in pregnancy that in lactation.