Glucosamine – what are its drug interactions?

Eimear Maguire, Senior Medicines Information Pharmacist, North West Medicines Information CentrePublished
  • This updated medicine Q&A considers the limited information available on potential drug interactions between glucosamine and conventional medicines.
  • There are a number of reports describing enhanced anticoagulant effects when glucosamine has been taken with warfarin. The mechanism of the interaction is unclear. The MHRA recommend that patients on warfarin should not take glucosamine. It has also been suggested that glucosamine should be used with caution in patients taking antiplatelet agents.  No reports of interaction between glucosamine and the NOACs were located; until more is known, caution is warranted.
  • There is a theoretical risk that glucosamine may interact with doxorubicin and etoposide; because of the potential clinical significance of this interaction, glucosamine should not be used concomitantly.
  • Glucosamine does not appear to adversely affect plasma blood glucose in patients without diabetes. However, data relating to its effects in patients with diabetes are limited. It would be prudent for patients with diabetes to monitor their blood glucose levels more closely if they start to take glucosamine, increase the dose or change the product being taken.
  • More research is required to identify which drugs interact with glucosamine supplements and to determine the significance of such interactions.