Pharmacy mix-up leads to pregnant woman taking methotrexate. What does this drug do?

A Colorado woman pregnant with her first child has an agonizing wait ahead. She was mistakenly given an abortion drug instead of antibiotics at a pharmacy last week and now must wait to see how this might affect her unborn child.

According to media reports, Mareena Silva, 19, took methotrexate, a cancer-fighting drug also used to terminate pregnancies, after a pharmacy said it mixed up her prescription with that of another patient.

So what is methothexate, and what does it do? The National Institutes of Health describes it as a dangerous drug. Here’s what it says on its MedlinePlus website:

“Methotrexate may cause very serious side effects. Some side effects of methotrexate may cause death. You should only take methotrexate to treat life-threatening cancer, or certain other conditions that are very severe and that cannot be treated with other medications. Talk to your doctor about the risks of taking methotrexate for your condition.”

The Feminist Women’s Health Center explains how it works as an abortion pill.

“Methotrexate is a chemotherapy agent that has been used for many years in the treatment of cancer because it affects cells that are rapidly dividing. In a Methotrexate (MTX) Abortion, it stops embryonic cells from dividing and multiplying and is a non-surgical method of ending pregnancy in its early stages. Within a few days or weeks of receiving an injection of Methotrexate (MTX) at the clinic, the pregnancy ends through an experience similar to an early miscarriage.”

And thedoctorwillseeyounow.com says this about high doses of the drug:

“Although in the high doses used in cancer treatment methotrexate poses a clear risk to a developing fetus, we do not know if the low dose of methotrexate used for medical abortion has a similar effect.”

Silva was treated at a hospital and released. She’s still pregnant, but the effects of the drug remain unknown.