I once bought the alcohol free Black-Walnut tincture and didn't think it was any different.
Where did You read that only alcohol based herbal extracts are good? You know in the alternative health world You can find an opposing view on almost everything.
Unfortunately it is true what sd2345 says and the tincture will be just a drop in the bucket when it comes to fighting parasites.
You could also buy some castor oil, because it is so important to keep the bowels moving.