Medications called prolactin inhibitors help to dry up the milk. I also know of a natural approach using sage from a health food store, which is also used for human mothers to dry up milk. People drink it as a tea, so I'm not sure about the specifics on how to give it to your dogs, but I do know that it has been given to dogs and helped dry up their milk. Here is the link to a site that I found when I looked it up, it's where I learned of the medication option for drying up milk: http://www.ehow.com/how_5042871_stop-lactating-dogs.html Here is another one titled "How to Stop Lactating in Dogs" : http://www.ehow.com/how_5042871_stop-lactating-dogs.html Medications called Lachesis and Cyclamen are used to reduce milk production as well. I hope this helps!