The amount of cladribine in milk is low with oral doses of 10 to 20 mg daily used in multiple sclerosis. Data in one patient indicates that the drug is rapidly eliminated over 24 hours and undetectable at 48 hours after a dose. Manufacturers recommend a 7-day (Europe) or 10-day (US) abstinence period. Chemotherapy may adversely affect the normal microbiome and chemical makeup of breastmilk.[1] Women who receive chemotherapy during pregnancy are more likely to have difficulty nursing their infant.[2]