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What’s the bioavailability of RSO suppositories?

What’s the bioavailability of RSO suppositories?

Getting the right answers in your cannabis journey can be tricky. But with The Cannigma’s Ask the Expert, you can find questions from readers like you, answered by a real cannabis pharmacist. 


Can you please share any information on the bioavailability of THC (aka RSO) suppositories? How much THC gets into the bloodstream?


Despite the stigma around suppositories, which are intended for rectal or vaginal administration, this dosage form is not uncommon and can be quite useful for treating both local and systemic issues.

As strange as it may sound, there is very little data evaluating the effects of cannabis infused suppositories. Most of the existing data suggest that THC is not well absorbed from the rectum, or not absorbed at all. Meaning that the suppositories wouldn’t get you high, and the effects would be local to the colon. Additionally, despite products on the market for vaginal THC and CBD suppositories, there is essentially no peer-reviewed research on the topic of cannabis-infused vaginal suppositories.

Specifically as it relates to RSO, there’s no research to lean on. We know that RSO is usually fully decarbed, THC-rich, and very concentrated (>50% THC). Even still, how much RSO to put in a suppository compared to another oil is a hard guess. But as always with RSO, use sparingly and try to be as accurate as possible, because it is so potent.

Regarding dosing, here is what I will say. Most products on the market are between 25 and 50mg of CBD or THC. Contrary to the evidence, the feeling of high has been reported in men and women who use suppositories. This is of course anecdotal evidence. We can really only go by what people are saying and basic pharmacology principles, which suggest THC could indeed be absorbed into the bloodstream with suppositories, at least to some extent. The doses involved in many of these unofficial reports I have heard range between 50mg and 200mg of THC to achieve psychoactivity, but again would depend on more factors including tolerance.

What is the bioavailability of infused suppositories? We don’t really know, but hopefully that helps give you a frame of reference. 

Codi Peterson, PharmD
Scientific advisor, The Cannigma
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  1. My husband has stage 4 pancan Mets to his abdominal cavity. Cancer is squeezing his bowel and he’s had NG tube for 2 weeks. Can RSO suppositories help him? We started using them yesterday and praying they do.

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