The Tox Lab

This week on The Tox Lab, we’re discussing poison dart frogs and the alkaloid epibatidine.

We begin by examining recent reports surrounding the death of Alexei Navalny and the suggestion that epibatidine may have been involved.

We then discuss poison dart frogs and the toxins found within them, including the discovery and isolation of epibatidine. From there, we explore its potent analgesic properties, how it acts at nicotinic acetylcholine receptors, and what makes it both pharmacologically interesting and highly toxic.

Finally, we examine attempts to develop epibatidine analogues as novel analgesics and explore the evolutionary question of how poison dart frogs themselves avoid poisoning.

Join us as we examine the pharmacology, toxicity, and evolving story surrounding epibatidine, and consider how a toxin derived from poison dart frogs became linked to drug development, toxicology, and international headlines.

Hope you enjoy!

Links to the papers we discussed:

https://www.gov.uk/government/news/joint-statement-by-the-uk-sweden-france-germany-and-the-netherlands-on-alexei-navalnys-death

https://pubs.rsc.org/en/content/articlelanding/2000/np/a900728h

https://www.science.org/doi/epdf/10.1126/science.aan5061

Check out our new website: https://thetoxlab.co.uk/

Disclaimer: All opinions are our own.

Find us on instagram: @the_tox_lab

Email us here: [email protected]

Support us here: https://buymeacoffee.com/thetoxlab

This week on The Tox Lab, we’re back with a long-awaited update on novel synthetic opioids.

We begin by discussing the April 2026 UNODC announcement on the increasingly varied forms in which synthetic opioids are being encountered, including vapes, powders, and counterfeit tablets marketed as benzodiazepines, oxycodone, and MDMA.

We then turn to the emergence of orphine analogues in both the UK and the US, discussing recent reports and trends associated with these compounds.

Finally, we examine a clinical case involving N-propionitrile chlorphine (cychlorphine), exploring the toxicological features and the challenges these emerging opioids present for clinicians, laboratories, and public health systems.

Join us as we examine the changing landscape of novel synthetic opioids, consider what these developments may mean for toxicology, harm reduction, and public health, and discuss where the market may be heading next.

Hope you enjoy!

This episode is very kindly sponsored by Cayman Chemical. Check out their Synthetic Opioid Analytical Standards Panel here: https://www.caymanchem.com/product/44436/synthetic-opioid-analytical-standards-panel-1

Links to papers we discussed:

https://www.unodc.org/LSS/Announcement/Details/973e194e-f8d6-4b4e-8aca-166aaec4ac7c

https://www.polizei.bayern.de/aktuelles/pressemitteilungen/100413/index.html

https://onlinelibrary.wiley.com/doi/10.1111/dar.70081

https://assets.publishing.service.gov.uk/media/69f3343fab602a88957eef2b/Seventh_addendum_to_the_ACMD_report_on_the_use_and_harms_of_2-benzyl-benzimidazole__nitazene__and_piperidine_benzimidazolone__brorphine-like__opioids_FINAL.pdf

https://www.cfsre.org/nps-discovery/public-alerts/increase-in-fatal-overdoses-linked-to-novel-synthetic-opioid-n-propionitrile-chlorphine-cychlorphine

https://www.tandfonline.com/doi/full/10.1080/15563650.2025.2594070

Link to our paper on N-pyrrolidino Isotonitazene: https://academic.oup.com/jat/advance-article-abstract/doi/10.1093/jat/bkag027/8663758?redirectedFrom=fulltext

Disclaimer: All opinions are our own.

Find us on instagram: @the_tox_lab

Email us here: [email protected]

Support us here: https://buymeacoffee.com/thetoxlab

This week on The Tox Lab, we are taking a look at the role of naloxone in risk taking behaviours, harm reduction and disparities surrounding naloxone access.

We begin by discussing a study looking at the expansion of naloxone access laws in the United States, exploring whether increased availability is associated with changes in heroin use among adolescents.

We then turn to a commentary paper examining the benefits and limitations of educating school children recognise an opioid overdose and administer naloxone.

Finally we discuss a paper investigating disparities in naloxone uptake amongst different ethnic and racial groups, and between individuals who inject versus smoke substances.

Join us as we explore the impact of naloxone access, education, and disparities, and consider what these findings mean for harm reduction and public health.

Hope you enjoy!

Links to the papers we discussed:

https://www.sciencedirect.com/science/article/abs/pii/S0955395923000294

https://onlinelibrary.wiley.com/doi/abs/10.1111/josh.70089

https://pubmed.ncbi.nlm.nih.gov/41428846/

Disclaimer: All opinions are our own.

Find us on instagram: @the_tox_lab

Email us here: [email protected]

Support us here: https://buymeacoffee.com/thetoxlab

A year after we first took a look at mitragynine (kratom), we are back with an update episode looking at how the landscape surrounding mitragynine is evolving.

We begin by examining poison centre data, exploring trends in reported exposures in the US and internationally, and the increase in its use.

We then discuss a case involving semi-synthetic mitragynine derivatives, including 7-hydroxymitragynine and mitragynine pseudoindoxyl, highlighting the clinical features including dose escalation, and challenges associated with withdrawal.

Finally, we turn to reports of combined use of kratom and kava, and consider how this may influence toxicity and withdrawal.

Join us as we examine emerging data, evolving patterns of use, and the clinical implications of mitragynine and its derivatives, and consider what these findings mean for toxicology and public health.

Hope you enjoy!

If you'd like us to cover an episode on Kava, please let us know in the comments!

Links to the papers we discussed:

https://www.cdc.gov/mmwr/volumes/75/wr/mm7511a1.htm

https://www.cureus.com/articles/467977-severe-early-onset-withdrawal-following-intentional-use-of-mitragynine-pseudoindoxyl-a-case-report-and-emerging-clinical-considerations#!/

https://www.cdc.gov/mmwr/volumes/75/wr/pdfs/mm7512a1-H.pdf

https://journals.lww.com/journaladdictionmedicine/abstract/9900/kava_potentiated_withdrawal_in_persons_using.687.aspx

Disclaimer: All opinions are our own.

Find us on instagram: @the_tox_lab

Email us here: [email protected]

Support us here: https://buymeacoffee.com/thetoxlab

This week on The Tox Lab, we’re examining the controversial 2006 Lancet paper on codeine and fatal opioid toxicity in a breastfed infant.

We begin by introducing the paper and the case at its centre, in which an infant developed fatal opioid toxicity following exposure to codeine via breast milk.

We then explore the proposed mechanism, focusing on the role of CYP2D6 metabolism and how variability in this pathway may lead to higher-than-expected morphine concentrations.

We also discuss the limitations and criticisms of the paper, including questions around causality, alternative explanations, and the extent to which pharmacogenetics alone can account for the outcome.

Finally, we consider the wider impact of this publication, including changes to clinical guidance, prescribing practices, and the ongoing debate around codeine use in breastfeeding individuals.

Join us as we examine the pharmacology, pharmacogenetics, and controversy surrounding this landmark case, and consider what this means for clinical toxicology and patient safety.

Hope you enjoy!

Links to the papers we discussed:

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(06)69255-6/abstract

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(26)00245-X/fulltext

https://www.thelancet.com/journals/lancet/article/PIIS0140673608612544/abstract https://ascpt.onlinelibrary.wiley.com/doi/10.1002/cpt.1882

Link to the New Yorker Article : https://www.newyorker.com/magazine/2026/02/02/did-a-celebrated-researcher-obscure-a-fatal-poisoning

Disclaimer: All opinions are our own.

Find us on instagram: @the_tox_lab

Email us here: [email protected]

Support us here: https://buymeacoffee.com/thetoxlab

This week on The Tox Lab, we’re examining pesticides and their role in toxicology.

We begin by discussing a study investigating pesticide exposure in florists, highlighting occupational risks and the potential for chronic low-level exposure.

We then turn to a paper analysing pesticide residue levels in commonly consumed fruits, including kiwifruit and bananas, and consider what this may mean for dietary exposure. Finally, we discuss a study examining pesticide-related fatalities in Turkey, exploring the clinical and toxicological features associated with these cases.

Join us as we explore the occupational, environmental, and clinical aspects of pesticide exposure, and consider what these findings mean for toxicology and public health.

Hope you enjoy!

Links to the papers we discussed:

https://pmc.ncbi.nlm.nih.gov/articles/PMC5451977/

https://www.sciencedirect.com/science/article/abs/pii/S0273230026000103?via%3Dihub

https://link.springer.com/article/10.1007/s12024-026-01220-x

Disclaimer: All opinions are our own.

Find us on instagram: @the_tox_lab

Email us here: [email protected]

Support us on: https://buymeacoffee.com/thetoxlab

This week on The Tox Lab, we continue our discussion on GHB, focusing on its role in forensic toxicology.

We begin by examining a study investigating GHB in drug‑facilitated crime in Paris, highlighting patterns of reported incidents and toxicological findings.

We then turn to post‑mortem toxicology, discussing the challenges of interpreting GHB concentrations after death and exploring research aimed at distinguishing post‑mortem formation from exogenous intake.

Join us as we explore the forensic applications, interpretive challenges, and analytical considerations associated with GHB, and consider how these factors impact casework.

This is part two of a two‑part series on GHB. In last week’s episode, we explored patterns of use, harms, and user perspectives.

Hope you enjoy!

Links to the papers we discussed:

https://www.sciencedirect.com/science/article/abs/pii/S0379073825003780?via%3Dihub

https://www.sciencedirect.com/science/article/pii/S2589871X24000925?via%3Dihub

https://www.sciencedirect.com/science/article/pii/S0379073825001306?via%3Dihub

Disclaimer: All opinions are our own.

Find us on instagram: @the_tox_lab

Email us here: [email protected]

This week on The Tox Lab, we’re examining GHB, its use, and the harms associated with it.

We begin by exploring what GHB is and how it works, before turning to a study from Australia examining trends in use over a 10-year period and the associated increase in harms.

We then discuss a qualitative study focusing on GHB use among individuals identifying as heterosexual, exploring patterns of use, motivations, and the ways in which users perceive and navigate risk, harm, and stigma.

Join us as we examine the pharmacology, patterns of use, and lived experiences associated with GHB, and consider what these findings may mean for understanding its risks.

This is part one of a two-part series. In next week’s episode, we will turn to the forensic aspects of GHB.

Hope you enjoy!

Links to the papers we discussed:

https://onlinelibrary.wiley.com/doi/10.1111/add.70308 https://link.springer.com/article/10.1186/s12954-026-01405-1

Disclaimer: All opinions are our own.

Find us on instagram: @the_tox_lab

Email us here: [email protected]

This week on The Tox Lab, we’re taking a closer look at poison centre data and how it can be used to identify drug trends and support toxicovigilance efforts.

We begin by discussing a study analysing data from six European poison centres in the Netherlands, Freiburg, Austria, Sweden, Switzerland and the UK. The paper examines reports involving the eleven most commonly encountered recreational drugs and highlights how patterns of drug use differ both over time and between countries.

We then turn to a study focusing on reports of novel psychoactive substances submitted to several European poison centres in 2021, exploring how these data can contribute to monitoring emerging substances and strengthening drug early warning systems.

Join us as we explore how poison centre data can provide valuable insights into drug use trends and play an important role in toxicology surveillance and public health.

Hope you enjoy!

Links to the papers we discussed:

https://www.tandfonline.com/doi/full/10.1080/15563650.2026.2628073

https://www.tandfonline.com/doi/full/10.1080/15563650.2024.2430311

Disclaimer: All opinions are our own.

Find us on instagram: @the_tox_lab

Email us here: [email protected]

This week on The Tox Lab, we’re taking a closer look at one of the world’s oldest drugs, alcohol, and some of the fatal complications associated with chronic misuse.

We discuss several cases that highlight the complex and sometimes unexpected consequences of long-term alcohol use, including hypokalaemic rhabdomyolysis, sudden unexpected death in individuals with alcohol misuse, and a fatal case of delirium tremens.

Using these cases, we explore the underlying mechanisms that may contribute to these outcomes and how chronic alcohol use can predispose individuals to severe and potentially fatal complications.

Join us as we examine the clinical features, mechanisms, and toxicological considerations surrounding the fatal consequences of chronic alcohol misuse.

Hope you enjoy!

Links to the papers we discussed:

https://www.sciencedirect.com/science/article/pii/S1344622326000556?casa_token=b4hFH3pyA7oAAAAA:f55en_CZh6ea1Wf-hG98mab7NfYlMWcqEy_c7SEyio08hDyy5eTwqwFwcMS029YHfZABlCOiMhQ

https://pmc.ncbi.nlm.nih.gov/articles/PMC12665443/

https://journals.sagepub.com/doi/abs/10.1177/00258172261419305

Disclaimer: All opinions are our own.

Find us on instagram: @the_tox_lab

Email us here: [email protected]