Pharmaceutical Expert Witness Opines on Methotrexate Toxicity

This case involves a twenty-four-year-old male who underwent a kidney transplantation. The patient was on dialysis and immunosuppressive therapy. He also had hypertension due to his renal manifestations. To manage his hypertension, his primary care physician prescribed the patient minoxidil 2.5 mg. Upon filling his prescription, the patient was given methotrexate (MTX) by the pharmacy, an immunosuppressive drug used to treat various diseases. Its mechanism of action is to interfere with cell growth. The physician must closely monitor the use of this drug in their patients. Throughout the course of his treatment, the patient was never prescribed methotrexate. The label on the prescription bottle was labeled with minoxidil, but contained 90 methotrexate tablets. After ingestion of the MTX for ten days, the patient became severely ill and was hospitalized. The diagnosis later was known to be MTX poisoning. The plaintiff alleged that the following injuries occurred due to MTX poisoning: fatigue, anasarca, congestive heart failure, coma, paralysis, multiple blood transfusions, dialysis, retrograde amnesia, tooth deterioration, physical and emotional distress.

Question(s) For Expert Witness

1. What are the long-term complications of methotrexate toxicity?

Expert Witness Response E-006915

This drug's mechanism works to inhibit cell growth. Along with their needed effects, medicines like methotrexate can sometimes cause unwanted effects such as blood problems, kidney problems, stomach or liver problems, loss of hair, and other side effects. Also, because of the way these medicines act on the body, there is a chance that they might cause other unwanted effects that may not occur until months or years after the medicine is used. These delayed effects may include certain types of cancer, such as leukemia. This drug is extremely dangerous and needs constant monitoring by the physician when being taken.