1. National Institute for Health and Care Excellence . Rheumatoid arthritis in adults: management (NG100) [online], 2020. Available: www.nice.org.uk/guidance/ng100 [Accessed 5 May 2021].
2. Scottish Intercollegiate Guidelines Network . Management of early rheumatoid arthritis: a national clinical guideline [online], 2011. Available: https://www.sign.ac.uk/media/1061/sign123.pdf [Accessed 5 May 2021].
3. The effect of folic acid and folinic acid supplements on purine metabolism in methotrexate-treated rheumatoid arthritis
4. Low-Dose Methotrexate: A Mainstay in the Treatment of Rheumatoid Arthritis
5. Methotrexate 2.5mg tablets . Summary of product characteristics. UK: Morningside Healthcare Ltd, 2020.