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The Rise and Risk of Delta-8 THC (Delta-8-Tetrahydrocannabinol)

  • Cannabis (B Sherman and R Tomko, Section Editors)
  • Published:
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Purpose of Review

The purpose of this review is to differentiate delta-8-tetrahydrocannabinol (delta-8) and delta-9-tetrahydrocannabinol (delta-9) as they relate to human health and disease.

Recent Findings

Delta-8 is a novel cannabinoid becoming increasingly used following the passage of the US Agricultural Improvement Act of 2018 and the deregulation of hemp. Cannabis spp. naturally produces little delta-8. Retail delta-8 products consist of synthetic delta-8 chemically converted from cannabidiol (CBD). Delta-8 marketing claims a “softer, gentler high” compared to delta-9, but limited data exist to support this claim. A recent screen of delta-8 products found that the majority contained heavy metal contamination and that the reported vs. actual compositions of commercial products did not agree.


The effects of delta-8 on the human body remain largely unexplored, as do the pharmacokinetic differences between delta-8 and delta-9. Because the dietary supplement market is largely unregulated, these products are not tested for contaminants that may also have harmful effects.

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This work was supported by a sponsored research agreement from PA Options for Wellness (a Pennsylvania-approved medical marijuana clinical registrant) and the Penn State Elliot S. Vesell endowment (both to KEV). The Penn State College of Medicine is a Pennsylvania-approved Academic Clinical Research Center.

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Correspondence to Kent E. Vrana.

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Nachnani, R., Raup-Konsavage, W.M. & Vrana, K.E. The Rise and Risk of Delta-8 THC (Delta-8-Tetrahydrocannabinol). Curr Addict Rep 9, 622–629 (2022).

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