"The reason I ask is that I have only found an article about a study that looked at rectal absorption in monkeys and they weren’t able to measure an effect.
Rectal suppositories are placed into the rectum and absorbed by the three haemorrhoidal veins. There aren’t sufficient studies on rectal absorption of cannabis, however the few studies that exist indicate that cannabis suppositories produce similar effects as oral administration. If you are interested in using rectal suppositories, I would recommend it for localized problems such as hemorrhoids. Cannabis suppositories should not be used as the primary treatment method, It should always be used in conjunction with other more proven methods such as tincutres, capes and capsules.