When weekly becomes daily: mucocutaneous ulceration and pancytopenia after a methotrexate dosing error

Rishikesh Dessai; Kunal Chawla; Shipra Gulati; Madangopal Paliwal

doi:10.18203/2394-6040.ijcmph20264233

Authors

Rishikesh Dessai Department of Internal Medicine, Sir Ganga Ram Hospital, New Delhi, India
Kunal Chawla Department of Internal Medicine, Sir Ganga Ram Hospital, New Delhi, India
Shipra Gulati Department of Internal Medicine, Sir Ganga Ram Hospital, New Delhi, India
Madangopal Paliwal Department of Internal Medicine, Sir Ganga Ram Hospital, New Delhi, India

DOI:

https://doi.org/10.18203/2394-6040.ijcmph20264233

Keywords:

Folinic acid, Medication error, Methotrexate, Mucositis, Pancytopenia

Abstract

The methotrexate is prescribed as a single dose per week for rheumatoid arthritis. It is dangerous if patient consumes the medication daily by mistake. We present a case of a 64-year-old female with diabetes with newly diagnosed rheumatoid arthritis who consumed 10 mg of methotrexate daily for five to six days instead of once weekly. In a few days the patient developed oral painful ulcers, difficulty in swallowing, bilateral leg ulcers with peeling of skin and fever. Blood tests showed pancytopenia, leucocytes were 1.75×10³/µl, platelets were 50×10³/µl. The methotrexate was stopped and gave 15 mg of intravenous folinic acid every sixth hourly for five days. Her platelets increased within four days. The oral and leg ulcers began to heal by the end of the first week. Skin ulcers are very uncommon manifestation of this toxicity - but clear instructions for weekly dosing can prevent this medication error.

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