The many uses of methotrexate

            The patient had an ectopic pregnancy in her fallopian tubes. She had presented in accident and emergency with symptoms of severe lower abdominal pain, vaginal bleeding and dizziness. An ultrasound had confirmed the diagnosis. Her human chorionic gondotropin levels were above 1000 IU/L.

I calculated the dose of methotrexate using the formula 50mg/m2. This was prescribed as a stat intramuscular dose. We had to monitor the patient’s creatinine, full blood counts and electrolytes before and after treatment.

            My advice to the patient was that she should not take any vitamin supplements that contain folic acid. The reason for this being that folic acid can make methotrexate less effective. I also advised her not to use any type of non-steroidal anti-inflammatory drug because they can stop methotrexate from leaving the body. I also made her aware of the possible teratogenic effects of methotrexate. That it would be safer to not conceive for the next six months.

This little episode taught me a little bit more about methotrexate.