Pilot study on cannabis-induced alterations in platelet function: implications for transfusion medicine.
Geneviève Laflamme1, Hind Hamzeh-Cognasse2, Fabrice Cognasse2,3
1Medical Affairs and Innovation, Héma-Québec, Québec, QC, Canada.
Platelets
|March 23, 2026
Summary
Cannabis joint extracts (CJE) alter platelet function in vitro, causing activation and impaired aggregation. This may impact transfusion safety and efficacy, requiring further in vivo investigation.
Area of Science:
- Hematology
- Pharmacology
- Immunology
Background:
- Platelet transfusions are critical for managing bleeding and hematologic disorders.
- Rising global cannabis use necessitates understanding its effects on blood products.
Purpose of the Study:
- To investigate the in vitro effects of cannabis joint extracts (CJE) on platelet function and transfusion safety.
- To assess CJE impact on platelet activation, mitochondrial function, and cytokine release.
Main Methods:
- Human platelets were exposed to two CJE with varying cannabinoid profiles.
- Assessed platelet activation (CD62P, Annexin V), mitochondrial depolarization, ATP levels, aggregation, and cytokine secretion (CCL3, PF4).
- Investigated receptor involvement (CB1, CB2) and signaling pathways (p38 MAPK, NF-κB), and endothelial cell activation.
Main Results:
- CJE induced dose-dependent platelet activation, mitochondrial stress, and impaired aggregation.
- Hemolysis was ruled out as the cause; receptor antagonists did not block activation.
- Observed activation of p38 MAPK and NF-κB pathways, elevated CCL3/PF4, and endothelial activation.
Conclusions:
- In vitro cannabis exposure alters platelet phenotype and signaling, potentially affecting transfusion efficacy and safety.
- Further in vivo studies are needed to confirm clinical relevance and establish exposure thresholds.
- Potential risks include reduced platelet efficacy or increased thrombotic complications in recipients.
