Synthetic Cannabinoid JWH-018 Caused Heart Damage, Arrhythmias, and Infarction-Like Changes in Rats | Research

The takeaway

The synthetic cannabinoid JWH-018 caused significant cardiovascular harm in rats, including arrhythmias, conduction blocks, ischemic damage, and myocardial infarction-like tissue changes, with effects worsening at higher doses and longer exposure.

Emergency medicine physicians, toxicologists, public health officials addressing synthetic cannabinoid use.

Synthetic cannabinoid JWH-018 caused myocardial infarction-like damage in rat hearts

What the researchers found

Acute high-dose JWH-018 caused bradycardia and hypotension. Subacute high-dose increased heart rate while continuing to lower blood pressure. JWH-018 induced arrhythmias, conduction blocks, ischemic ECG changes, and prolonged QT intervals. Histopathology revealed myocardial infarction-like features including contraction bands and ischemic damage. Elevated pro-BNP indicated cardiac stress. JWH-018 and metabolites were detected directly in heart tissue.

Why it matters

Synthetic cannabinoids have been linked to sudden cardiac deaths in humans but the mechanisms have been unclear. This study provides comprehensive evidence of dose- and duration-dependent cardiovascular toxicity, including direct detection of the compound in heart tissue.

The numbers in context

JWH-018 at 0.5 mg/kg (low) and 5 mg/kg (high); 14-day subacute exposure; acute high-dose: bradycardia + hypotension; subacute high-dose: tachycardia + hypotension + prolonged QT; myocardial infarction-like histopathology; elevated pro-BNP and triglycerides; drug detected in heart tissue.

How the study worked

Wistar albino rats divided into five groups: control, acute low-dose (0.5 mg/kg), acute high-dose (5 mg/kg), subacute low-dose (0.5 mg/kg for 14 days), and subacute high-dose (5 mg/kg for 14 days). Assessed via echocardiography, hemodynamics, ECG, histopathology, biochemical markers, and LC-MS/MS heart tissue analysis.

What this study cannot tell us

Rat cardiovascular physiology differs from humans. Doses may not correspond to human consumption patterns. JWH-018 is one of many synthetic cannabinoids with varying properties. Controlled laboratory exposure differs from real-world use patterns.

How to read the evidence

Preliminary: Comprehensive animal study with multiple assessment methods including tissue drug detection, but rat cardiovascular results need human correlation.

When this study was published

Published in 2025.

The bigger picture

This study reinforces that synthetic cannabinoids should not be considered safe alternatives to natural cannabis. The cardiovascular damage documented here, including potential for fatal arrhythmias and ischemic heart damage, aligns with clinical reports of young people experiencing heart attacks after synthetic cannabinoid use.

Questions still open

Are the cardiovascular effects reversible with cessation? Do other synthetic cannabinoids produce similar cardiac damage? What is the minimum dose and duration that produces clinically significant heart effects?

Common questions

How dangerous are synthetic cannabinoids for the heart?

This study shows JWH-018 caused dose-dependent heart damage including arrhythmias, conduction blocks, and tissue changes resembling a heart attack. The drug was found directly in heart tissue. Clinical reports of sudden cardiac death in synthetic cannabinoid users are consistent with these findings.

Are synthetic cannabinoids the same as cannabis?

No. Synthetic cannabinoids are laboratory-created chemicals that bind to cannabinoid receptors but are structurally different from natural cannabis compounds. They are often much more potent and carry significantly greater health risks, as this study demonstrates for cardiovascular effects.

Read the original research

Acute and subacute cardiovascular effects of synthetic cannabinoid JWH-018 in rat.

Forensic toxicology, 43(2), 266-279

View on PubMed ↗Publisher’s paper ↗

Citation

Ozhan, Onural; Ermis, Necip; Celbis, Osman; Samdanci, Emine; Petekkaya, Semih; Oruc, Mucahit; Soylu, Ozcan; Koparir, Pelin; Acet, Ahmet; Parlakpinar, Hakan. (2025). Acute and subacute cardiovascular effects of synthetic cannabinoid JWH-018 in rat.. Forensic toxicology, 43(2), 266-279. https://doi.org/10.1007/s11419-025-00720-9