What Is THCP-O? Structure, Effects, and Risks

It’s not surprising, following the exit of THC-O from the hemp market, that another popular cannabinoid would arrive in acetate form.

THC-O, the acetate ester form of THC, had a brief moment in the spotlight as a competitor to delta 8 THC and HHC, among other hemp-derived market competitors. But the discovery that heating an acetate like THC-O creates dangerous ketene gas, and the Drug Enforcement Administration's (DEA) determination that THC-O is not a natural hemp constituent, made the cannabinoid risky to sell (and use!).

Acylating THCP, possibly one of the strongest cannabinoids in existence, was an obvious next move—but not necessarily the wisest. Heating and inhaling any acetate ester can seriously damage the lungs—and that includes THCP-O and HHC-O. If you want to try these novel acetate cannabinoids, use only edibles or tinctures. Never vape or smoke acetates. (For more info, check the note at the top of our THC-O article.)

Hemp-derived cannabis products have become increasingly potent. Delta 8 THC was a modest start, but standards are shifting as the industry matures and users gain a clearer sense of what’s possible. Where does THCP-O fit in?

What is THCP-O?

Tetrahydrocannabiphorol acetate (THCP-O-acetate or THCP-O) is the acetate ester form of THCP, a potent cannabinoid that caught the eye of hemp researchers back in 2019. THCP is famous for its seemingly unmatched binding affinity with the CB1 receptor. 

CB1 receptors are found throughout the human endocannabinoid system (ECS), particularly in the brain and spinal cord. The more readily a substance binds to these nervous system hotspots, the more likely it is to get you high. 

Identifying THCP as psychotropic was the easy part. From there, it’s been a matter of exploring the intensity of the THCP high, and the effects it creates when consumed by actual users. Research is scant, though compared to THCP-O, THCP isn’t too poorly documented. 

Everything we know about THCP-O comes from anecdotes, claims by prospective sellers, and speculation. 

Structurally, THCP-O merges the key features of THCP with those of acetate cannabinoids like THC-O and HHC-O. It shares the THCP molecule’s massive seven-carbon side chain (two atoms more than delta 9 THC’s chain), but unlike THCP, THCP-O has an acetate group. 

There’s no evidence that THCP-O forms naturally in cannabis. Without intervention in a lab, it’s unlikely that this cannabinoid would see the light of day. That probably means that the DEA will view it as illegal, as it does THC-O.

Does THCP-O get you high?

THCP-O will absolutely get you high. What's less clear is how THCP-O’s potency compares to THCP and THC-O, or even other niche acetate esters like HHC-O. 

Some cannabis sellers have reported that THCP is over thirty times as potent as delta 9 THC and, thus, can get its users thirty times as high. That’s not exactly correct. 

Researchers suspect that THCP binds to CB1 receptors thirty times more effectively than delta 9. That might mean you’ll get thirty times higher—or it might mean you’ll get twice as high, or maybe not even that. We don't know exactly how the binding affinity translates into the strength of the high. It’s all just a guess. Anecdotally, however, users report that THCP is highly intoxicating.

Don’t let yourself get too wrapped up in claims about THCP-O’s potency. A few sources lump it in with THCP and say that it’s thirty times more potent than marijuana-derived delta 9 THC, but zero research supports the claim—just anecdotes and speculation.

What are the effects of THCP-O?

As it stands, claims about THCP-O's effects are more in line with THCP than THC-O. You won’t find the word “psychedelic” thrown around as much, but plenty cite that THCP-O is extremely potent due to its seven-atom side chain. 

By the way, even THC-O may or may not be psychedelic. Opinions are split, but according to a 2023 poll, few users report having that experience. Don’t expect anything too trippy out of THCP-O, either.

THCP-O is psychotropic. That's evident in its structural crossover with THCP and THC-O, as well as user anecdotes. Its specific effects, including benefits and potential adverse responses, are unknown. 

Just to be extra clear, never vape or smoke THCP-O, or any product that contains any amount of THCP-O. 

If you consume it—in edible or tincture form—make sure to ease your way into the session. Start with a small dose, wait for the effects to settle in, then take more to taste. 

Potent cannabinoids can elevate your risk of an adverse reaction. If you’re regularly dealing with bad highs, or have poor responses to alt cannabinoids in general, be especially wary of THCP-O. Not only are its effects hard to predict, but they could be much more intense than those of other hemp-derived cannabinoids.

Is THCP-O safe?

Whether THCP-O is safe to consume in edibles or oils is unclear, but it definitely isn’t safe to vape or smoke. Vapers should stay far away from acetates of any kind. 

Cannabinoids in acetate form, like THC-O and CBD-O, are known to convert into ketene gas when exposed to temperatures over 644 °F (340 °C). The same thing happens with all acetate substances. The infamous “EVALI” lung injury outbreak in 2019 was caused by weed vapers inhaling ketene formed by black market THC carts diluted with vitamin E acetate. 

Ketene is a dangerous lung toxicant, and you put yourself at risk by inhaling any amount of it, whether or not the consequences are instantly severe or noticeable.

Untested vape products are often packed with cheap fillers and additives. But in the case of THCP-O it is the primary active substance that could cause severe lung damage.

Without third-party testing and a certificate of analysis (COA), there’s no way to verify a product’s purity or lack of fillers. But even that’s not enough when it comes to acetates. Additive-free or not, acetate esters are risky and should be avoided in weed carts. 

Stay away from acetates to minimize your risk of serious, permanent lung injury, even when the cannabinoid in question is hyped up by sellers. There are plenty of safer options on the market.