- Chondroitin used alone has not been associated with any serious adverse effects; however there is a lack of robust evidence from long-term studies.
- Adverse effects that have been noted with chondroitin are generally mild and primarily gastrointestinal in nature.
- Effects that have been reported in studies include nausea, epigastralgia, diarrhoea, constipation, skin symptoms, eyelid oedema, lower limb oedema, alopecia and extrasystoles (causality not established).
- There is a theoretical risk of prolonged bleeding time with chondroitin.
- Exacerbation of asthma was noted in a woman who took a glucosamine-chondroitin preparation. It is unknown which, if either, ingredient caused this effect. Cautious use of chondroitin is recommended in patients with asthma. Patients should be aware of the possibility of asthma symptoms worsening on starting chondroitin/glucosamine.
- Hepatotoxicity has been reported in patients taking chondroitin in combination with other supplements, however there is insufficient evidence to assess the extent to which chondroitin contributed to these adverse effects.
Senior Information Pharmacist, Welsh Medicines Information Centre