Can terpenes and/or terpenoids replace paracetamol and NSAID’s when treating pain in osteoarthritis – a review

Background: Terpenes and terpenoids, naturally occurring compounds derived from plants, have shown potential in various therapeutic applications due to their anti-inflammatory, antioxidant, and analgesic properties. This review tries to elucidate the potential of terpenes and terpenoids in managing pain for patients with osteoarthritis in the knee and/or hip, and whether they can function as alternatives to conventional painkillers including paracetamol and NSAID’s. Methods: A systematic literature review was conducted, resulting in the inclusion of ten studies, each either examining different classifications of terpenes and terpenoids alone or in combination with other bioactive compounds through various experimental designs. These studies were primarily assessed for their impact on pain reduction and secondary for possible impact on joint stiffness, activity of daily living and consumption of rescue medication. Results: In eight out of ten studies, plant extracts containing terpenes and terpenoids significantly decreased overall pain, resulting in improvement in outcome measures such as WOMAC, VAS and LFI scores. A decline in joint stiffness and inflammation was observed in the remaining studies. It is proposed that cyclic triterpenoids, in particular, because of anti-inflammatory properties, may play a crucial role in pain management in osteoarthritis. It is also suggested that monoterpenes, diterpenes, and sesquiterpenes alone or in combination with other bioactive compounds, can have significant impact on pain. Conclusion: Because of the variability in study design, dosages, duration of treatment and the fact that there at present are no human studies focusing on “pure” terpenes and/or terpenoids, it is difficult to conclude that a specific classification of terpenes and terpenoids would be effective. However, our findings emphasizes that terpenes and terpenoids should be further investigated as they in the future may partly replace rescue medication.