Guidance for Pharmacists on Safe Supply of Oral Methotrexate

The purpose of this guidance is to highlight the need for extra vigilance when dispensing methotrexate to patients. Incorrect dispensing, prescribing and use of methotrexate can result in significant patient morbidity and mortality, due to severe adverse effects, which can occur abruptly. Such cases have been reported in Ireland and elsewhere and are of concern to all individuals involved in the supply of methotrexate.  

These cases have primarily related to overdosage with oral methotrexate, where errors occurred in the prescribing, dispensing or use of the drug, most commonly where the drug was taken daily rather than weekly. Other cases of patient harm have resulted from confusion between the different strengths of oral methotrexate tablets; cases of deliberate overdosage have also been reported.  

Errors in dosing may, in some cases, have been compounded by a lack of monitoring for recognised side effects and symptoms of toxicity.