Recommendations for the use of methotrexate in rheumatoid arthritis: up and down scaling of the dose and administration routes.

Objectives: To describe the optimal therapeutic strategy for use of methotrexate in RA patients over the initial dose, route of administration, dose increase and decrease, patient monitoring, and use of folic/folinic acid.

Material And Method: Eleven clinical experts proposed some questions to be solved. A systematic literature search was conducted. The contents were selected in a work session and subsequently validated via email to establish the level of agreement.

Results: The initial dose of methotrexate should not be <10mg/week, preferably orally, but considering the parenteral route as an alternative due to compliance, non effectiveness of treatment or gastrointestinal side effects, polypharmacy, obesity (if required doses are >20mg/week), patient preference, very active disease or to avoid administration errors. Changing to a parenteral administration is proposed when the oral route is not effective enough, gastrointestinal toxicity appears, there is non-compliance or due to cost-effectiveness reasons before using more expensive drugs. On the contrary, due to patient preferences, intolerance to injections, dose reduction <7.5mg/week, non effectiveness of the route, poor compliance or gastrointestinal side effects. There should be a rapid dose escalation if inadequate responses occurr up to 15-20 or even 25mg/week in about 8 weeks, with increments of 2.5-5mg. The reduction will be carried out according to the dose the patient had, with decreases of 2.5-5mg every 3-6 months. Patient monitoring should be performed every 1-1.5 months until stability and then every 1-3 months.

Conclusions: This document pretends to solve some common clinical questions and facilitate decision-making in RA patients treated with methotrexate.