Oral Methotrexate now included in HPRA’s Interchangeable List

The HPRA has published a list of interchangeable medicines of oral formulations of Methotrexate.

Methotrexate is a potent immunosuppressant used in the treatment of active rheumatoid arthritis in adults, severe recalcitrant psoriasis and some oncological indications. Oral methotrexate for rheumatological and dermatological indications is administered on a once-weekly basis. 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.

Pharmacists play a critical role in ensuring the safe use of methotrexate, through their participation in the educating, counselling and monitoring of patients. This role is particularly important when supplying a substitute medicinal product. Therefore, when a medicine is substituted, pharmacists must take time to ensure that patients receive appropriate information and advice so as to ensure that patients understand the correct use of their medicines and are advised on any change in name or appearance etc.

The PSI has issued Guidance for Pharmacists on Safe Supply of Oral Methotrexate which includes the below key points. Pharmacists must show extra vigilance when dispensing methotrexate to patients and are asked to ensure they address these points to ensure the safe supply of this medicine to patients:

• Pharmacists should personally supply the appropriately labelled methotrexate to the patient/carer and should verbally confirm the dosage requirements with the patient/carer, reinforcing the labelled instructions in a clear manner. This understanding must be confirmed by the patient/carer.
• When a medicine is substituted, pharmacists must take time to ensure that patients receive appropriate information and advice so as to ensure that patients understand the correct use of their medicines and are advised on any change in name, number of tablets or appearance etc. of their medicine.
• The dispensed methotrexate should be labelled with the number of tablets, total dose, weekly intervals, and day of week on which it is to be taken i.e. ‘Take six x 2.5mg tablets (15mg in total) once a week on a Friday.’
• Patients/ carers should be informed of the potential risks of serious adverse reactions in the case of an overdose and of the signs and symptoms of toxicity.