- Crohn's disease
- methotrexate has been used effectively with azathioprine unresponsive Crohn's disease - including fistulating Crohn's disease 
 - treatment with methotrexate in low dosage offers an effective alternative to thiopurine maintenance in patients with Crohn's disease 
 - do not offer azathioprine, mercaptopurine or methotrexate as monotherapy to induce remission (1)
 
 
In patients who have failed to respond to steroids, or who are intolerant of azathioprine or 6-mercaptopurine, methotrexate has been shown to induce remission of inflammatory bowel disease in 40 per cent of patients
- there is no evidence for the use of lower-dose oral methotrexate
 - methotrexate is as efficacious in inducing remission as azathioprine, but it does not appear to work any faster
 
NICE state with respect to use of methotrexate in Crohn's disease: (1)
- Add-on treatment in Crohn's disease. Maintenance treatment for those who choose this option
- methotrexate
- consider addition of methotrexate to a conventional glucocorticosteroid or budesonide to induce remission in people who cannot tolerate azathioprine or mercaptopurine, or in whom TPMT activity is deficient, if:
- there are two or more inflammatory exacerbations in a 12-month period, or
 - the glucocorticosteroid dose cannot be tapered
 
 
 - only consider methotrexate to maintain remission in people who: 
- needed methotrexate to induce remission, or
 - have tried but did not tolerate azathioprine or mercaptopurine for maintenance, or
 - have contraindications to azathioprine or mercaptopurine (for example, deficient TPMT activity or previous episodes of pancreatitis)
 
 
 
Methotrexate must be stopped in those planning pregnancy (2). 
Reference:
- NICE. Crohn’s disease: management. NICE guideline NG129. Published May 2019
 - Torres J, Bonovas S, Doherty G, et al. ECCO guidelines on therapeutics in Crohn's disease: medical treatment. J Crohns Colitis. 2020 Jan 1;14(1):4-22.