I am by no means a medical professional so take anything I say with a grain of salt. As the liver is the primary filtration system it is largely responsible for detoxifying blood (among other things but this seems most important for this question). A damaged liver will obviously perform this task worse so it would seem an easier target for toxic substances to afflict the bloodstream in greater quality. It would also depend on the severity of the disease, how far along it is, what exactly the disease is, etc. Liver disease can also cause nausea and vomiting and vomiting would impact SN usage but a high enough dose would hopefully counteract that. So, as far as I know, I don't believe it would negatively affect the method, but I only know so much so don't take my word as gospel.