Preclinical Evidence for a Drug-Drug Interaction Between Cannabinol and Melatonin.

Area of Science:

• Pharmacology
• Drug Metabolism
• Cannabinoid Research

Background:

• Increased use of medicinal cannabis products containing minor cannabinoids like cannabinol (CBN).
• CBN is often marketed for sleep benefits, sometimes in combination with melatonin.
• Cannabinoids are known inhibitors of drug-metabolizing enzymes, suggesting potential drug-drug interactions (DDIs).

Purpose of the Study:

• To investigate if cannabinol (CBN) inhibits the metabolism of melatonin mediated by the enzyme CYP1A2.
• To assess the in vitro and in vivo effects of CBN on melatonin metabolism.

Main Methods:

• In vitro experiments to assess CBN's inhibition of CYP1A2-mediated melatonin metabolism.
• In vivo studies in mice to evaluate the pharmacokinetic interaction between CBN and melatonin.

Main Results:

• Cannabinol (CBN) potently inhibited the CYP1A2-mediated metabolism of melatonin in vitro.
• In vivo, CBN administration significantly increased the oral bioavailability of melatonin in mice.
• Plasma exposure to melatonin increased four-fold in the presence of CBN.

Conclusions:

• Cannabinol (CBN) has the potential to cause a pharmacokinetic drug-drug interaction with melatonin.
• This interaction involves the inhibition of CYP1A2-mediated melatonin metabolism.
• Healthcare providers should be aware of this potential DDI when patients use both CBN and melatonin.