Cannabidiol oil – potential adverse effects and drug interactions

  • Due to an increasing popularity of self-administration of over-the-counter bought CBD, doctors and pharmacists should be aware of its potential adverse effects and interactions.
  • The most common adverse effects found in studies were somnolence, decreased appetite, vomiting, diarrhoea and elevated liver enzymes.
  • Moderate to severe impairment of kidney or liver function may theoretically reduce the clearance and/or excretion of CBD.
  • The data available suggests that CBD interacts with cytochrome p450 enzymes consequently, caution is recommended when CBD is co-administered with medications that are metabolised by this pathway.
  • Readers should consult the UKMi Q&A Cannabis based medicinal products potential drug interactions for further information on potential drug interactions.
  • Information regarding CBD safety is limited to few human studies and information should be interpreted cautiously. Further studies are needed to evaluate the full safety profile.
Complementary and alternative therapiesDrug interactionsMedicines Safety