Metabolites of the deadly synthetic cannabinoid 5F-MDMB-PINACA retain potency and show unusual CB1 receptor behavior

The synthetic cannabinoid 5F-MDMB-PINACA (linked to over 40 deaths) produces metabolites that remain active at CB1 receptors with unusual pharmacological properties, potentially explaining why this drug is so toxic.

Cabanlong, Christian V et al.·Toxicological sciences : an official journal of the Society of Toxicology·2022·Moderate EvidenceAnimal StudyAnimal Study
RTHC-03736Animal StudyModerate Evidence2022RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Animal Study
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

5F-MDMB-PINACA and its metabolite M2 showed nanomolar affinity and high efficacy at CB1 receptors. Metabolite M7 retained high efficacy but only micromolar affinity. The CB1 antagonist rimonabant blocked these compounds differently than it blocks THC. Chronic exposure caused CB1 receptor down-regulation, but only the parent compound produced desensitization. M2 produced dose-dependent hypothermia and analgesia in mice comparable to THC.

Key Numbers

Over 40 fatalities associated with 5F-MDMB-PINACA. Parent compound and M2 had nM affinity; M7 had only μM affinity. Rimonabant showed different antagonism profiles for synthetic cannabinoids vs. THC.

How They Did This

Competition binding and G-protein modulation studies at CB1 receptors. Rimonabant antagonism experiments compared to THC. Chronic administration studies measuring receptor down-regulation and desensitization. In vivo locomotor, hypothermia, and analgesia tests in mice for M2 and THC.

Why This Research Matters

Understanding why synthetic cannabinoids like 5F-MDMB-PINACA are so much more dangerous than THC requires understanding their metabolites. The atypical pharmacology described here may explain the severe and sometimes fatal toxicity.

The Bigger Picture

The finding that metabolites of synthetic cannabinoids retain activity and behave differently from THC metabolites at CB1 receptors helps explain why synthetic cannabinoids produce prolonged, severe, and unpredictable effects compared to plant cannabis.

What This Study Doesn't Tell Us

In vitro and mouse studies. The pharmacological differences observed may not fully explain human toxicity. M7 concentrations in vivo may not reach the μM levels needed for activity. Limited to CB1 receptor; other targets not examined.

Questions This Raises

  • ?Do the active metabolites accumulate to toxic levels in humans?
  • ?Could the atypical antagonism profile explain why standard treatments fail in synthetic cannabinoid overdose?
  • ?Are there better antidotes than rimonabant?

Trust & Context

Key Stat:
Linked to 40+ deaths; metabolites show atypical CB1 receptor behavior
Evidence Grade:
Rigorous pharmacological characterization with in vitro and in vivo components, relevant to understanding synthetic cannabinoid toxicity.
Study Age:
Published in 2022.
Original Title:
Metabolites of Synthetic Cannabinoid 5F-MDMB-PINACA Retain Affinity, Act as High Efficacy Agonists and Exhibit Atypical Pharmacodynamic Properties at CB1 Receptors.
Published In:
Toxicological sciences : an official journal of the Society of Toxicology, 187(1), 175-185 (2022)
Database ID:
RTHC-03736

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal StudyOne case or non-human subjects
This study

Tests effects in animals (usually mice or rats), not humans.

What do these levels mean? →

Frequently Asked Questions

Why are synthetic cannabinoids more dangerous than natural cannabis?

This study shows that 5F-MDMB-PINACA and its metabolites are high-efficacy agonists at CB1 receptors (vs. THC which is partial), produce atypical receptor interactions, and the metabolites remain active. This combination may lead to prolonged, severe, and sometimes fatal effects.

What is 5F-MDMB-PINACA?

Also known as 5F-ADB, it is a third-generation synthetic cannabinoid that has been associated with over 40 deaths worldwide. It is much more potent and pharmacologically distinct from THC.

Read More on RethinkTHC

Cite This Study

RTHC-03736·https://rethinkthc.com/research/RTHC-03736

APA

Cabanlong, Christian V; Russell, Lauren N; Fantegrossi, William E; Prather, Paul L. (2022). Metabolites of Synthetic Cannabinoid 5F-MDMB-PINACA Retain Affinity, Act as High Efficacy Agonists and Exhibit Atypical Pharmacodynamic Properties at CB1 Receptors.. Toxicological sciences : an official journal of the Society of Toxicology, 187(1), 175-185. https://doi.org/10.1093/toxsci/kfac024

MLA

Cabanlong, Christian V, et al. "Metabolites of Synthetic Cannabinoid 5F-MDMB-PINACA Retain Affinity, Act as High Efficacy Agonists and Exhibit Atypical Pharmacodynamic Properties at CB1 Receptors.." Toxicological sciences : an official journal of the Society of Toxicology, 2022. https://doi.org/10.1093/toxsci/kfac024

RethinkTHC

RethinkTHC Research Database. "Metabolites of Synthetic Cannabinoid 5F-MDMB-PINACA Retain A..." RTHC-03736. Retrieved from https://rethinkthc.com/research/cabanlong-2022-metabolites-of-synthetic-cannabinoid

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.