Black Walnut is not really for Liver Cleanses but to clear any isochonic or systematic fungal or bacterial infections such as candida.
Your most typical liver cleanse begins with grapefruit juice and oil. That is all you need. If you are looking for a bit more advanced, it will include Epson Salt.
Should be fine.
By the way, if you want to get over nut allergies or any type of allergies, it is merely a inflammatory response. Most people say they can die if they eat peanuts or what not. I used to be allergic too. There have been a few record-breaking studies that show starting to eat whatever you are allergic to in very low quantities and building it up over the weeks will reduce the inflammation response and allow you to eat it.