That is not such as strange thing to do- the rectum garlic insert. I just read a book by MArk Konlee for AIDS and CIDS (which I have) and it is recommended in this book. It is called a 'Colon Implant'. I consume garlic regularly and this seemed to work better than eating it. I now dip mine in Oregano oil. Be careful that you don't use full strength- ouch!!!
The other good way of eating garlic for cleansing reasons (also recommended in this book) was to eat a few cloves then follow it by a couple of teaspoons of pysillium in water. This gives a sustained release of garlic through the system.
I don't know what I would do without garlic. If I don't eat it I break out in herpes and feel so unwell.